Gypsum panel including natural fiber material

Abstract

The present invention is directed to gypsum panels containing a natural fiber material layer and a method of making such gypsum panels. The gypsum panel may include a gypsum core, a first facing material, and a second facing material. The natural fiber material layer may be one or more of the first facing material, the second facing material, or an additional layer. The natural fiber material layer comprises plant-derived fibers. The methods of the present invention are directed to making the aforementioned gypsum panels.

Description

Atty. Docket No.: NGCGB-139 GYPSUM PANEL INCLUDING NATURAL FIBER MATERIAL RELATED APPLICATIONS

[0001] The present application is based on and claims priority to U.S. Provisional Patent Application Serial No.63 / 651,439, filed on May 24, 2024, which is incorporated herein by reference in its entirety. BACKGROUND

[0002] Gypsum panels are commonly employed in drywall construction of interior walls and ceilings and also have other applications. Generally, these gypsum panels are formed from a gypsum slurry including a mixture of calcined gypsum, water, and other conventional additives. The mixture is cast and allowed to set by reaction of the stucco with the water. Notably, walls and ceilings incorporating gypsum panels may have poor acoustical performance, which may result in noise pollution, lack of privacy, and similar issues in the various spaces of a building. Further, walls and ceilings incorporating gypsum panels may have poor thermal insulative properties, which may result in increased heating and cooling costs and inadequate temperature stability.

[0003] While gypsum panels currently exist that provide sound damping and thermal insulation, there is still a need to further improve the acoustical and thermal performance of the panels and provide improved sound damping and thermal insulation. SUMMARY OF THE INVENTION

[0004] Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.

[0005] In accordance with one embodiment of the present invention, a gypsum panel is disclosed. The gypsum panel comprises: a gypsum core comprising gypsum; and a first facing material and a second facing material, the first facing material, the second facing material, or both comprising a natural fiber material layer comprising plant- derived fibers in an amount of about 20 wt.% or more, the plant-derived fibers being derived from leaves, stems, bark, roots, seeds, fruits, or a combination thereof of one or more plants.Atty. Docket No.: NGCGB-139

[0006] In some aspects, the plant-derived fibers are derived from the bark of one or more plants. In some aspects, the plant-derived fibers are cork fibers.

[0007] In some aspects, the natural fiber material layer comprises plant-derived fibers in an amount of about 30 wt.% or more, such as about 40 wt.% or more, such as about 50 wt.% or more.

[0008] In some aspects, the natural fiber material layer has a thickness of about 1 inch or less, such as about 1 / 2 inch or less.

[0009] In some aspects, the gypsum panel has a thermal resistance of about 0.04 K- m2 / W or more as determined in accordance with ASTM C518-17.

[0010] In some aspects, the gypsum panel has a thermal resistivity of about 3.0 K- m / W or more as determined in accordance with ASTM C518-17.

[0011] In some aspects, the gypsum panel has an apparent thermal conductivity of about 0.04 W / m-K or more as determined in accordance with ASTM C518-17.

[0012] In accordance with another embodiment of the present invention, a gypsum panel is disclosed. The gypsum panel comprises: a gypsum core comprising gypsum, the gypsum core being formed from a gypsum slurry, the gypsum core comprising two or more gypsum core layers; a first facing material and a second facing material; and a natural fiber material layer positioned between at least two of the two or more gypsum core layers, the natural fiber material layer comprising plant-derived fibers in an amount of about 20 wt.% or more, the plant-derived fibers being derived from leaves, stems, bark, roots, seeds, fruits, or a combination thereof of one or more plants; wherein at least a portion of a thickness of the natural fiber material layer is penetrated by the gypsum slurry.

[0013] In some aspects, the plant-derived fibers are derived from the bark of one or more plants. In some aspects, the plant-derived fibers are cork fibers.

[0014] In some aspects, the natural fiber material layer comprises plant-derived fibers in an amount of about 30 wt.% or more, such as about 40 wt.% or more, such as about 50 wt.% or more.

[0015] In some aspects, the natural fiber material layer has a thickness of about 1 inch or less, such as about 1 / 2 inch or less.Atty. Docket No.: NGCGB-139

[0016] In some aspects, the gypsum panel has a thermal resistance of about 0.04 K- m2 / W or more as determined in accordance with ASTM C518-17.

[0017] In some aspects, the gypsum panel has a thermal resistivity of about 3.0 K- m / W or more as determined in accordance with ASTM C518-17.

[0018] In some aspects, the gypsum panel has an apparent thermal conductivity of about 0.04 W / m-K or more as determined in accordance with ASTM C518-17.

[0019] In accordance with one embodiment of the present invention, a method of making a gypsum panel is disclosed. The method comprises: providing a first facing material; depositing a gypsum slurry comprising stucco and water onto the first facing material; providing a second facing material on the gypsum slurry; and allowing the stucco to convert to calcium sulfate dihydrate; wherein the gypsum panel comprises a natural fiber material layer, the natural fiber material layer comprising plant-derived fibers in an amount of about 20 wt.% or more, the plant-derived fibers being derived from leaves, stems, bark, roots, seeds, fruits, stalks, branches, trunks, or a combination thereof of one or more plants. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The invention will now be described, by way of example, with reference to the accompanying drawings, in which:

[0021] FIG.1 illustrates a front view of one embodiment of a gypsum panel in accordance with aspects of the present subject matter; and

[0022] FIG.2 illustrates a front view of one embodiment of a gypsum panel in accordance with aspects of the present subject matter.

[0023] Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the present invention. DETAILED DESCRIPTION

[0024] Reference now will be made in detail to various embodiments. Each example is provided by way of explanation of the embodiments, not as a limitation of the present disclosure. In fact, it will be apparent to those skilled in the art that variousAtty. Docket No.: NGCGB-139 modifications and variations can be made to the embodiments without departing from the scope or spirit of the present disclosure. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that aspects of the present disclosure cover such modifications and variations.

[0025] Generally speaking, the present disclosure is directed to a gypsum panel containing natural fiber material, such as a natural fiber material layer, and a method of making such gypsum panel. In particular, the gypsum panel can include one or more natural fiber material layers and a gypsum core. The gypsum panel may also include one or more facing materials. As used herein, “a natural fiber material layer” is a layer comprising one or more plant-derived fibers. The present inventors have discovered that the gypsum panel disclosed herein can have various benefits due to the use of a natural fiber material layer. For instance, the present inventors have discovered that the natural fiber material layer can enhance the acoustical performance, such as sound damping, and / or the thermal performance, such as the heat resistance, of a gypsum panel.

[0026] It should be understood that throughout the entirety of this specification, each numerical value (e.g., weight percentage, concentration) disclosed should be read as modified by the term “about”, unless already expressly so modified, and then read again as not to be so modified. For instance, a value of “100” is to be understood as disclosing “100” and “about 100”. Further, it should be understood that throughout the entirety of this specification, when a numerical range (e.g., weight percentage, concentration) is described, any and every amount of the range, including the end points and all amounts therebetween, is disclosed. For instance, a range of “1 to 100”, is to be understood as disclosing both a range of “1 to 100 including all amounts therebetween” and a range of “about 1 to about 100 including all amounts therebetween”. The amounts therebetween may be separated by any incremental value.

[0027] It should be understood that, unless stated otherwise, any standard listed herein (e.g., ASTM) is the most recent version available as of the latest revision year. Further, it should be understood that throughout the entirety of this specification, theAtty. Docket No.: NGCGB-139 term “and / or” refers to one or all of the listed components or a combination of any two or more of the listed components. Notably, some aspects of the present invention may omit one or more of the features disclosed herein.

[0028] In general, a gypsum panel formed in accordance with the present disclosure may include a gypsum core. Generally, the gypsum core may be sandwiched by facing materials (e.g., first facing material, second facing material). The facing materials may include any facing material as generally employed in the art. For instance, the facing material may be a paper facing material, a fibrous (e.g., glass fiber) mat facing material (e.g., glass mat facing material), a metal facing material (e.g., an aluminum facing material), or a polymeric facing material. In general, the first facing material and the second facing material may be the same type of material. Alternatively, the first facing material may be one type of material while the second facing material may be a different type of material. In one aspect, the first facing material and the second facing material may comprise the same binder (e.g., a polymeric binder). In another aspect, the first facing material and the second facing material may comprise a different binder. In an additional aspect, the first facing material and / or the second facing material may not comprise a polymeric binder.

[0029] In general, a glass mat facing material in one embodiment may be coated. However, in one particular embodiment, the glass mat facing material may not have a coating, such as a coating that is applied to the surface of the mat.

[0030] In some aspects, a facing material may be a natural fiber material layer. For instance, as illustrated in FIG.1, a gypsum panel 10 may include a gypsum core 12, a natural fiber material layer 14 as a first facing material, and a second facing material 16. Generally, a natural fiber material layer may be utilized as a first facing material, a second facing material, or both.

[0031] Notably, a facing material in accordance with the present disclosure may be a multilayer facing material. A multilayer facing material formed in accordance with the present disclosure may include one or more natural fiber material layers. In general, one or more layers of the multilayer facing material may include paper, fiberglass, one or more metals, one or more polymers, or a combination thereof. In this respect, a multilayer facing material may include one or more natural fiber material layers, one orAtty. Docket No.: NGCGB-139 more paper layers, one or more fiberglass layers, one or more metal layers, one or more polymer layers, or a combination thereof.

[0032] Generally, the multilayer facing material may include two or more layers, such as three or more layers, such as four or more layers, such as five or more layers. In general, a multilayer facing material may have six layers or less, such as five layers or less, such as four layers or less, such as three layers or less. In general, a multilayer facing material formed in accordance with the present disclosure may have an outer facing material layer and an inner facing material layer. Notably, the inner facing material layer and / or the outer facing material layer may be a natural fiber material layer. The “inner facing material layer” is the layer of a multilayer facing material that is closest (e.g., adjacent) to a gypsum core and / or gypsum core layer. The “outer facing material layer” is the multilayer facing material layer opposite the inner facing material layer. The outer facing material layer faces away from the gypsum core. In this respect, the outer facing material layer is not adjacent to the gypsum core.

[0033] In general, two or more layers of a multilayer facing material may sandwich one or more layers of a multilayer facing material. Notably, two or more layers that sandwich one or more layers may be made of the same material or may be made of different material. For instance, when two or more layers of a multilayer facing material sandwich one or more layers and are made of the same material, the two layers may be paper layers.

[0034] In some aspects, one or more natural fiber material layers may be positioned between two or more gypsum core layers, such as a first gypsum core layer and a second gypsum core layer. Generally, one or more natural fiber material layers may be positioned adjacent to one or more gypsum core layers, such as a first gypsum core layer and a second gypsum core layer. Notably, one or more natural fiber material layers may be non-adjacent to one or more of the facing materials (e.g., first facing material, second facing material) of the gypsum panel. Referring now to FIG.2, FIG.2 illustrates a gypsum panel 10 including a first facing material 18, a second facing material 16, a first gypsum core layer 20, a second gypsum core layer 22, and a natural fiber material layer 14. Notably, the natural fiber material layer 14 is between the first gypsum core layer 20 and the second gypsum core layer 22. Further, the natural fiberAtty. Docket No.: NGCGB-139 material layer 14 is adjacent to the first gypsum core layer 20 and the second gypsum core layer 22.

[0035] Notably, a gypsum slurry and / or any components thereof may penetrate at least a portion of the thickness of a natural fiber material layer. In general, the gypsum slurry and / or any components thereof may penetrate or be present in a natural fiber material layer by about 0% to about 100% of the thickness of the natural fiber material layer, such as about 0% or more, such as about 10% or more, such as about 20% or more, such as about 30% or more, such as about 40% or more, such as about 50% or more, such as about 60% or more, such as about 70% or more, such as about 80% or more, such as about 90% or more, such as about 100% or less, such as about 90% or less, such as about 80% or less, such as about 70% or less, such as about 60% or less, such as about 50% or less, such as about 40% or less, such as about 30% or less, such as about 20% or less, such as about 10% or less. It should be understood that a gypsum slurry and / or any components thereof may penetrate at least a portion of the thickness of a natural fiber material layer that is present in a facing material or as a facing material. It should be understood that a gypsum slurry and / or any components thereof may penetrate at least a portion of the thickness of a natural fiber material layer that is present between two or more gypsum core layers.

[0036] In some aspects, the gypsum slurry and / or any components thereof may penetrate or be present in a natural fiber material layer by about 0% to about 50%, such as about 1% to about 40%, such as about 1% to about 30%, such as about 1% to about 25% of the thickness of the natural fiber material layer.

[0037] In general, the natural fiber material layer may include plant-derived fibers from the leaves, stems, bark, roots, seeds, fruits, stalks, branches, trunks, or a combination thereof of one or more plants. Notably, the natural fiber material layer may comprise bast fibers, leaf fibers, seed fibers, bark fibers, reed fibers, or a combination thereof. For instance, the natural fiber material layer may comprise bast fibers such as jute fibers, flax fibers, hemp fibers, ramie fibers, kenaf fibers, or a combination thereof. Further, for instance, the natural fiber material layer may comprise leaf fibers such as banana fibers, sisal fibers, agave fibers, pineapple fibers, or a combination thereof. Additionally, for instance, the natural fiber material layer may comprise seed fibers suchAtty. Docket No.: NGCGB-139 as coir fibers, cotton fibers, kapok fibers, or a combination thereof. Notably, for instance, the natural fiber material layer may comprise bark fibers such as cork fibers. Further, for instance, the natural fiber material layer may comprise reed fibers such as wheat fibers, corn fibers, rice fibers, or a combination thereof.

[0038] In some aspects, the natural fiber material layer may comprise fiber from one or more angiosperm plants. For instance, the natural fiber material layer may comprise jute fibers, flax fibers, hemp fibers, ramie fibers, kenaf fibers, banana fibers, sisal fibers, agave fibers, pineapple fibers, coir fibers, cotton fibers, kapok fibers, cork fibers, xylem, or a combination thereof.

[0039] In general, a natural fiber material layer may comprise natural fibers (i.e., plant-derived fibers), such as any of the fibers or fiber types (e.g., bark fibers) disclosed herein, in an amount of about 10 wt.% or more, such as about 20 wt.% or more, such as about 30 wt.% or more, such as about 40 wt.% or more, such as about 50 wt.% or more, such as about 60 wt.% or more, such as about 70 wt.% or more, such as about 80 wt.% or more, such as about 90 wt.% or more. Generally, a natural fiber material layer may comprise natural fibers, such as one or more of the fibers or fiber types disclosed herein, in an amount of about 100 wt.% or less, such as about 90 wt.% or less, such as about 80 wt.% or less, such as about 70 wt.% or less, such as about 60 wt.% or less, such as about 50 wt.% or less, such as about 40 wt.% or less, such as about 30 wt.% or less, such as about 20 wt.% or less, such as about 10 wt.% or less.

[0040] In some aspects, a natural fiber material layer may comprise natural fibers (i.e., plant-derived fibers), such as any of the fibers or fiber types (e.g., bark fibers) disclosed herein, in an amount of about 10 wt.% to about 100 wt.%, such as about 25 wt.% to about 100 wt.%, such as about 50 wt.% to about 100 wt.%.

[0041] Generally, a natural fiber material layer may have a thickness of 0.05 inches or more, such as 0.10 inches or more, such as 0.15 inches or more, such as 0.20 inches or more, such as 0.25 inches or more, such as 0.30 inches or more, such as 0.35 inches or more, such as 0.40 inches or more, such as 0.45 inches or more, such as 0.50 inch or more, such as 0.55 inches or more, such as 0.60 inches or more, such as 0.65 inches or more, such as 0.70 inches or more, such as 0.75 inches or more, such as 0.80 inches or more, such as 0.85 inches or more, such as 0.90 inches orAtty. Docket No.: NGCGB-139 more. In general, the thickness of a natural fiber material layer may be 1 inch or less, such as 0.95 inches or less, such as 0.90 inches or less, such as 0.85 inches or less, such as 0.80 inches or less, such as 0.75 inches or less, such as 0.70 inches or less, such as 0.65 inches or less, such as 0.60 inches or less, such as 0.55 inches or less, such as 0.50 inches or less, such as 0.45 inch or less, such as 0.40 inches or less, such as 0.35 inches or less, such as 0.30 inches or less, such as 0.25 inches or less, such as 0.20 inches or less, such as 0.15 inches or less, such as 0.10 inches or less.

[0042] In some aspects, a natural fiber material layer may have a thickness of about 0.05 inches to about 1 inch, such as about 0.05 inches to about 0.80 inches, such as about 0.1 inches to about 0.8 inches, such as about 0.2 inches to about 0.8 inches.

[0043] In general, a natural fiber material layer may have a thickness that is at least 5% larger than the thickness of the gypsum core or one or more gypsum core layers (e.g., first gypsum core layer, second gypsum core layer) of a gypsum panel, such as about 10% larger or more, such as about 15% larger or more, such as about 20% larger or more, such as about 30% larger or more, such as about 40% larger or more. Generally, a natural fiber material layer may have a thickness that is at least 5% smaller than the thickness of the gypsum core or one or more gypsum core layers (e.g., first gypsum core layer, second gypsum core layer) of a gypsum panel, such as about 10% smaller or less, such as about 15% smaller or less, such as about 20% smaller or less, such as about 30% smaller or less, such as about 40% smaller or less, such as about 50% smaller or less.

[0044] In some aspects, the density of a natural fiber material layer may be less than the density of the gypsum core or one or more gypsum core layers (e.g., first gypsum core layer, second gypsum core layer) of a gypsum panel. In some aspects, the density of a natural fiber material layer may be more than the density of the gypsum core or one or more gypsum core layers (e.g., first gypsum core layer, second gypsum core layer) of a gypsum panel.

[0045] Generally, a gypsum panel incorporating one or more natural fiber material layers may have enhanced thermal resistance, thermal resistivity, apparent thermal conductivity, or a combination thereof as compared to traditional gypsum panels. The thermal properties of the gypsum panel of the present disclosure may be determinedAtty. Docket No.: NGCGB-139 using means in the art. The thermal properties of the gypsum panel (e.g., thermal resistance, thermal resistivity, apparent thermal conductivity) may be determined or tested in accordance with ASTM C518-17, which is a standard test method of steady- state thermal transmission properties by means of a heat flow meter apparatus. The heat flow meter utilized may be a LaserComp FOX 304 heat flow meter.

[0046] Notably, the inclusion of one or more natural fiber material layers in the gypsum panel may improve the thermal resistance of the gypsum panel. For instance, the thermal resistance of the gypsum panel may be from about 0.01 K-m2 / W to about 0.6 K-m2 / W, including all increments of about 0.01 K-m2 / W therebetween. Generally, the thermal resistance of the gypsum panel may be about 0.02 K-m2 / W or more, such as about 0.04 K-m2 / W or more, such as about 0.06 K-m2 / W or more, such as about 0.08 K-m2 / W or more, such as about 0.10 K-m2 / W or more, such as about 0.12 K-m2 / W or more, such as about 0.14 K-m2 / W or more, such as about 0.16 K-m2 / W or more, such as about 0.18 K-m2 / W or more, such as about 0.20 K-m2 / W or more, such as about 0.22 K-m2 / W or more, such as about 0.24 K-m2 / W or more, such as about 0.26 K-m2 / W or more, such as about 0.28 K-m2 / W or more, such as about 0.30 K-m2 / W or more, such as about 0.32 K-m2 / W or more, such as about 0.34 K-m2 / W or more, such as about 0.36 K-m2 / W or more, such as about 0.38 K-m2 / W or more, such as about 0.40 K-m2 / W or more, such as about 0.42 K-m2 / W or more, such as about 0.44 K-m2 / W or more, such as about 0.46 K-m2 / W or more, such as about 0.48 K-m2 / W or more, such as about 0.50 K-m2 / W or more, such as about 0.52 K-m2 / W or more, such as about 0.54 K-m2 / W or more, such as about 0.56 K-m2 / W or more, such as about 0.58 K-m2 / W or more. In general, the thermal resistance of the gypsum panel may be about 0.60 K-m2 / W or less, such as about 0.58 K-m2 / W or less, such as about 0.56 K-m2 / W or less, such as about 0.54 K-m2 / W or less, such as about 0.52 K-m2 / W or less, such as about 0.50 K-m2 / W or less, such as about 0.48 K-m2 / W or less, such as about 0.46 K-m2 / W or less, such as about 0.44 K-m2 / W or less, such as about 0.42 K-m2 / W or less, such as about 0.40 K- m2 / W or less, such as about 0.38 K-m2 / W or less, such as about 0.36 K-m2 / W or less, such as about 0.34 K-m2 / W or less, such as about 0.32 K-m2 / W or less, such as about 0.30 K-m2 / W or less, such as about 0.28 K-m2 / W or less, such as about 0.26 K-m2 / W or less, such as about 0.24 K-m2 / W or less, such as about 0.22 K-m2 / W or less, such asAtty. Docket No.: NGCGB-139 about 0.20 K-m2 / W or less, such as about 0.18 K-m2 / W or less, such as about 0.16 K- m2 / W or less, such as about 0.14 K-m2 / W or less, such as about 0.12 K-m2 / W or less, such as about 0.10 K-m2 / W or less, such as about 0.08 K-m2 / W or less, such as about 0.06 K-m2 / W or less, such as about 0.04 K-m2 / W or less.

[0047] In some aspects, the thermal resistivity of the gypsum panel may be from about 1.0 K-m / W to about 20.0 K-m / W, including all increments of about 0.1 K-m / W therebetween. Generally, the thermal resistivity of the gypsum panel may be about 1.0 K-m / W or more, such as about 3.0 K-m / W or more, such as about 5.0 K-m / W or more, such as about 6.0 K-m / W or more, such as about 7.0 K-m / W or more, such as about 8.0 K-m / W or more, such as about 9.0 K-m / W or more, such as about 10.0 K-m / W or more, such as about 11.0 K-m / W or more, such as about 12.0 K-m / W or more, such as about 13.0 K-m / W or more, such as about 14.0 K-m / W or more, such as about 15.0 K-m / W or more, such as about 16.0 K-m / W or more, such as about 17.0 K-m / W or more, such as about 18.0 K-m / W or more, such as about 19.0 K-m / W or more. In general, the thermal resistivity of the gypsum panel may be 20.0 K-m / W or less, such as about 19.0 K-m / W or less, such as about 18.0 K-m / W or less, such as about 17.0 K-m / W or less, such as about 16.0 K-m / W or less, such as about 15.0 K-m / W or less, such as about 14.0 K- m / W or less, such as about 13.0 K-m / W or less, such as about 12.0 K-m / W or less, such as about 11.0 K-m / W or less, such as about 10.0 K-m / W or less, such as about 9.0 K-m / W or less, such as about 8.0 K-m / W or less, such as about 7.0 K-m / W or less, such as about 6.0 K-m / W or less, such as about 5.0 K-m / W or less.

[0048] In some aspects, the apparent thermal conductivity of the gypsum panel may be from about 0.01 W / m-K to about 0.6 W / m-K, including all increments of about 0.01 W / m-K therebetween. Generally, the apparent thermal conductivity of the gypsum panel may be about 0.01 W / m-K or more, such as about 0.02 W / m-K or more, such as about 0.04 W / m-K or more, such as about 0.06 W / m-K or more, such as about 0.08 W / m-K or more, such as about 0.10 W / m-K or more, such as about 0.12 W / m-K or more, such as about 0.14 W / m-K or more, such as about 0.16 W / m-K or more, such as about 0.18 W / m-K or more, such as about 0.20 W / m-K or more, such as about 0.22 W / m-K or more, such as about 0.24 W / m-K or more, such as about 0.26 K- W / m-K or more, such as about 0.28 W / m-K or more, such as about 0.30 W / m-K or more, such asAtty. Docket No.: NGCGB-139 about 0.32 W / m-K or more, such as about 0.34 W / m-K or more, such as about 0.36 W / m-K or more, such as about 0.38 W / m-K or more, such as about 0.40 W / m-K or more, such as about 0.42 W / m-K or more, such as about 0.44 W / m-K or more, such as about 0.46 W / m-K or more, such as about 0.48 W / m-K or more, such as about 0.50 W / m-K or more, such as about 0.52 W / m-K or more, such as about 0.54 W / m-K or more, such as about 0.56 W / m-K or more, such as about 0.58 W / m-K or more. In general, the apparent thermal conductivity of the gypsum panel may be about 0.60 W / m-K or less, such as about 0.58 W / m-K or less, such as about 0.56 W / m-K or less, such as about 0.54 W / m-K or less, such as about 0.52 W / m-K or less, such as about 0.50 W / m-K or less, such as about 0.48 W / m-K or less, such as about 0.46 W / m-K or less, such as about 0.44 W / m-K or less, such as about 0.42 W / m-K or less, such as about 0.40 W / m-K or less, such as about 0.38 W / m-K or less, such as about 0.36 W / m- K or less, such as about 0.34 W / m-K or less, such as about 0.32 W / m-K or less, such as about 0.30 W / m-K or less, such as about 0.28 W / m-K or less, such as about 0.26 W / m-K or less, such as about 0.24 W / m-K or less, such as about 0.22 W / m-K or less, such as about 0.20 W / m-K or less, such as about 0.18 W / m-K or less, such as about 0.16 W / m-K or less, such as about 0.14 W / m-K or less, such as about 0.12 W / m-K or less, such as about 0.10 W / m-K or less, such as about 0.08 W / m-K or less, such as about 0.06 W / m-K or less, such as about 0.04 W / m-K or less.

[0049] As indicated herein, the present inventors have discovered that the natural fiber material as disclosed herein may be effective in improving the acoustical performance of a gypsum panel thereby reducing the transmission of noise. For instance, in comparison to conventional gypsum panel, in particular an existing, installed gypsum panel without a natural fiber material layer, the gypsum panel as disclosed herein may exhibit a sound transmission loss of 5% or more, such as about 10% or more, such as about 15% or more, such as about 20% or more, such as about 25% or more, such as about 30% or more, such as about 35% or more, such as about 40% or more, such as about 45% or more, such as about 50% or more and less than 100%, such as about less than 90%, such as about less than 80%, such as about 70% or less, such as about 60% or less in comparison to the conventional gypsum panel without a natural fiber material layer. Such comparison may be at any frequency and inAtty. Docket No.: NGCGB-139 particular at a frequency of 100 Hz or more, such as about 125 Hz or more, such as about 500 Hz or more, such as about 1000 Hz or more, such as about 2000 Hz or more, such as about 2500 Hz or more, such as about 3150 Hz or more, such as about 4000 Hz or more. In particular, such comparison may be at 100 Hz, such as about 125 Hz, such as about at 500 Hz, such as about at 1000 Hz, such as about at 2000 Hz, such as about at 2500 Hz, such as about at 3150 Hz, such as about at 4000 Hz. In addition, such comparison may be at any 2, such as about at any 3, such as about at any 4, such as about at any 5 of the aforementioned frequencies.

[0050] Further, the sound transmission loss for a wall assembly including the gypsum panel as disclosed herein and as conducted in accordance with ASTM E90 may result in an STC rating of 20 or more, such as about 25 or more, such as about 30 or more, such as about 35 or more, such as about 40 or more, such as about 45 or more, such as about 50 or more, such as about 55 or more, such as about 60 or more. The STC rating may be less than 70, such as about 65 or less, such as about 60 or less, such as about 55 or less, such as about 50 or less, such as about 45 or less, such as about 40 or less. Such comparison may be determined based on a frequency curve as identified in ASTM E90.

[0051] In addition, at a frequency of 1000 Hz, the sound transmission loss of the gypsum panel as disclosed herein may be 55 dB or more, such as about 56 dB or more, such as about 57 dB or more, such as about 58 dB or more, such as about 60 dB or more. At a frequency of 2000 Hz, the sound transmission loss of the gypsum panel as disclosed herein may be more than 50 dB, such as about 51 dB or more, such as about 52 dB or more, such as about 53 dB or more, such as about 55 dB or more, such as about 57 dB or more. At a frequency of 4000 Hz, the sound transmission loss of the gypsum panel as disclosed herein may be more than 52 dB, such as about 53 dB or more, such as about 55 dB or more, such as about 57 dB or more, such as about 59 dB or more, such as about 60 dB or more.

[0052] In general, the gypsum core may comprise calcium sulfate dihydrate. The gypsum used to make the gypsum core may be from a natural source, a synthetic source, and / or from reclaim and is thus not necessarily limited by the present invention. In general, the gypsum, in particular the calcium sulfate dihydrate, may be present inAtty. Docket No.: NGCGB-139 the gypsum core in an amount of at least 50 wt.%, such as at least 60 wt.%, such as at least 70 wt.%, such as at least 80 wt.%, such as at least 90 wt.%, such as at least 95 wt.%, such as at least 98 wt.%, such as at least 99 wt.%. The gypsum may be present in an amount of 100 wt.% or less, such as 99 wt.% or less, such as 98 wt.% or less, such as 95 wt.% or less, such as 90 wt.% or less based on the weight of the solids in the gypsum slurry. In one embodiment, the aforementioned weight percentages are based on the weight of the gypsum core. In another embodiment, the aforementioned weight percentages are based on the weight of the gypsum panel.

[0053] In some aspects, the gypsum core may also comprise other cementitious materials. These cementitious materials may include calcium sulfate anhydrite, land plaster, cement, fly ash, or any combination thereof. When present, they may be utilized in an amount of 30 wt.% or less, such as 25 wt.% or less, such as 20 wt.% or less, such as 15 wt.% or less, such as 10 wt.% or less, such as 8 wt.% or less, such as 5 wt.% or less based on the total content of the cementitious material.

[0054] In general, the composition of the gypsum core is not necessarily limited and may include any additives as known in the art. For instance, the additives may include dispersants, foam or foaming agents including aqueous foam (e.g. sulfates), set accelerators (e.g., ball mill accelerator, land plaster, sulfate salts, etc.), set retarders, binders, biocides (such as bactericides and / or fungicides), adhesives, pH adjusters, thickeners (e.g., silica fume, Portland cement, fly ash, clay, celluloses, high molecular weight polymers, etc.), leveling agents, non-leveling agents, colorants, fire retardants or additives (e.g., silica, silicates, expandable materials such as vermiculite, perlite, etc.), water repellants (e.g., waxes, silicones, siloxanes, etc.), fillers (e.g., glass spheres, glass fibers), natural and synthetic fibers (e.g. cellulosic fibers, microfibrillated fibers, nanocellulosic fibers, etc.), acids (e.g., boric acid), secondary phosphates (e.g., condensed phosphates or orthophosphates including trimetaphosphates, polyphosphates, and / or cyclophosphates, etc.) and / or other phosphate derivatives (e.g., fluorophosphates, etc.), natural and synthetic polymers, starches (e.g., pregelatinized starch, non-pregelatinized starch, and / or a modified starch, such as an acid modified starch), sound dampening polymers (e.g., viscoelastic polymers / glues, such as those including an acrylic / acrylate polymer, etc.; polymers with low glass transitionAtty. Docket No.: NGCGB-139 temperature, etc.), and mixtures thereof. In general, it should be understood that the types and amounts of such additives are not necessarily limited by the present invention.

[0055] Each additive of the gypsum core may be present in the gypsum core in an amount of 0.0001 wt.% or more, such as 0.001 wt.% or more, such as 0.01 wt.% or more, such as 0.02 wt.% or more, such as 0.05 wt.% or more, such as 0.1 wt.% or more, such as 0.15 wt.% or more, such as 0.2 wt.% or more, such as 0.25 wt.% or more, such as 0.3 wt.% or more, such as 0.5 wt.% or more, such as 1 wt.% or more, such as 2 wt.% or more. The additive may be present in an amount of 20 wt.% or less, such as 15 wt.% or less, 10 wt.% or less, such as 7 wt.% or less, such as 5 wt.% or less, such as 4 wt.% or less, such as 3 wt.% or less, such as 2.5 wt.% or less, such as 2 wt.% or less, such as 1.8 wt.% or less, such as 1.5 wt.% or less, such as 1 wt.% or less, such as 0.8 wt.% or less, such as 0.6 wt.% or less, such as 0.5 wt.% or less, such as 0.4 wt.% or less, such as 0.35 wt.% or less, such as 0.3 wt.% or less, such as 0.2 wt.% or less, such as 0.15 wt.% or less. The weight percentage may be based on the weight of the gypsum panel. Further, the weight percentage may be based on the weight of the gypsum core. In a further embodiment, such weight percentage may be based on the weight of a respective gypsum core layer. In an even further embodiment, the aforementioned weight percentages may be based on the solids content of the gypsum slurry. Moreover, the aforementioned weight percentages may be based on the weight of the stucco in the gypsum slurry. Additionally, the aforementioned weight percentages may be based on the weight of the gypsum in the gypsum core. In yet another embodiment, the aforementioned weight percentages may be based on the weight of the gypsum in the respective gypsum core layer.

[0056] In general, a gypsum panel formed in accordance with the present disclosure may be formed from a method as disclosed herein. For instance, in the method of making a gypsum panel, a first facing material may be provided wherein the first facing material has a first facing material surface and a second facing material surface opposite the first facing material surface. The first facing material may be conveyed on a conveyor system (i.e., a continuous system for continuous manufacture of gypsum panel). Thereafter, a gypsum slurry may be provided or deposited onto the first facingAtty. Docket No.: NGCGB-139 material in order to form and provide a gypsum core. Next, a second facing material may be provided onto the gypsum slurry. The first facing material, the gypsum core, and the second facing material may then be dried simultaneously. Next, the first facing material, the gypsum core, and the second facing material may be cut such that the first facing material, the gypsum core, and the second facing material form a gypsum panel.

[0057] In general, the composition of the gypsum slurry is not necessarily limited and may be any generally known in the art. Generally, in one embodiment, the gypsum core is made from a gypsum slurry including at least stucco and water.

[0058] In general, stucco may be referred to as calcined gypsum or calcium sulfate hemihydrate. The calcined gypsum may be from a natural source, a synthetic source, and / or reclaim and is thus not necessarily limited by the present invention. In addition to the stucco, the gypsum slurry may also contain some calcium sulfate dihydrate or calcium sulfate anhydrite. If calcium sulfate dihydrate is present, the hemihydrate is present in an amount of at least 50 wt.%, such as at least 60 wt.%, such as at least 70 wt.%, such as at least 80 wt.%, such as at least 85 wt.%, such as at least 90 wt.%, such as at least 95 wt.%, such as at least 98 wt.%, such as at least 99 wt.% based on the weight of the calcium sulfate hemihydrate and the calcium sulfate dihydrate. Furthermore, the calcined gypsum may be anhydrite (e.g., AII, AIII), α-hemihydrate, β- hemihydrate, or a mixture thereof.

[0059] In addition to the stucco, the gypsum slurry may also contain other cementitious materials. These cementitious materials may include calcium sulfate anhydrite, land plaster, cement, fly ash, or any combination thereof. When present, they may be utilized in an amount of 30 wt.% or less, such as 25 wt.% or less, such as 20 wt.% or less, such as 15 wt.% or less, such as 10 wt.% or less, such as 8 wt.% or less, such as 5 wt.% or less based on the total content of the cementitious material.

[0060] As indicated above, the gypsum slurry may include water. Water may be employed for fluidity and also for rehydration of the gypsum to allow for setting.

[0061] The weight ratio of the water to the stucco may be 0.1 or more, such as 0.2 or more, such as 0.2 or more, such as 0.3 or more, such as 0.4 or more, such as 0.5 or more, such as 0.6 or more, such as 0.7 or more. The water to stucco weight ratio may be 4 or less, such as 3.5 or less, such as 3 or less, such as 2.5 or less, such as 2 orAtty. Docket No.: NGCGB-139 less, such as 1.7 or less, such as 1.5 or less, such as 1.4 or less, such as 1.3 or less, such as 1.2 or less, such as 1.1 or less, such as 1 or less, such as 0.9 or less, such as 0.85 or less, such as 0.8 or less, such as 0.75 or less, such as 0.7 or less, such as 0.6 or less, such as 0.5 or less, such as 0.4 or less, such as 0.35 or less, such as 0.3 or less, such as 0.25 or less, such as 0.2 or less.

[0062] In addition to the stucco and the water, the gypsum slurry may also include any other conventional additives as known in the art. In this regard, such additives are not necessarily limited by the present invention. For instance, the additives may include dispersants, foam or foaming agents including aqueous foam (e.g. sulfates), set accelerators (e.g., ball mill accelerator, land plaster, sulfate salts, etc.), set retarders, binders, biocides (such as bactericides and / or fungicides), adhesives, pH adjusters, thickeners (e.g., silica fume, Portland cement, fly ash, clay, celluloses, high molecular weight polymers, etc.), leveling agents, non-leveling agents, colorants, fire retardants or additives (e.g., silica, silicates, expandable materials such as vermiculite, perlite, etc.), water repellants (e.g., waxes, silicones, siloxanes, etc.), fillers (e.g., glass spheres, glass fibers), natural and synthetic fibers (e.g. cellulosic fibers, microfibrillated fibers, nanocellulosic fibers, etc.), acids (e.g., boric acid), secondary phosphates (e.g., condensed phosphates or orthophosphates including trimetaphosphates, polyphosphates, and / or cyclophosphates, etc.) and / or other phosphate derivatives (e.g., fluorophosphates, etc.), natural and synthetic polymers, starches (e.g., pregelatinized starch, non-pregelatinized starch, and / or a modified starch, such as an acid modified starch), sound dampening polymers (e.g., viscoelastic polymers / glues, such as those including an acrylic / acrylate polymer, etc.; polymers with low glass transition temperature, etc.), and mixtures thereof. In general, it should be understood that the types and amounts of such additives are not necessarily limited by the present invention.

[0063] Each additive of the gypsum slurry may be present in the gypsum slurry in an amount of 0.0001 wt.% or more, such as 0.001 wt.% or more, such as 0.01 wt.% or more, such as 0.02 wt.% or more, such as 0.05 wt.% or more, such as 0.1 wt.% or more, such as 0.15 wt.% or more, such as 0.2 wt.% or more, such as 0.25 wt.% or more, such as 0.3 wt.% or more, such as 0.5 wt.% or more, such as 1 wt.% or more,Atty. Docket No.: NGCGB-139 such as 2 wt.% or more. The additive may be present in an amount of 20 wt.% or less, such as 15 wt.% or less, 10 wt.% or less, such as 7 wt.% or less, such as 5 wt.% or less, such as 4 wt.% or less, such as 3 wt.% or less, such as 2.5 wt.% or less, such as 2 wt.% or less, such as 1.8 wt.% or less, such as 1.5 wt.% or less, such as 1 wt.% or less, such as 0.8 wt.% or less, such as 0.6 wt.% or less, such as 0.5 wt.% or less, such as 0.4 wt.% or less, such as 0.35 wt.% or less, such as 0.3 wt.% or less, such as 0.2 wt.% or less, such as 0.15 wt.% or less. The weight percentage may be based on the weight of the gypsum panel. Further, the weight percentage may be based on the weight of the gypsum core. In a further embodiment, such weight percentage may be based on the weight of a respective gypsum core layer. In an even further embodiment, the aforementioned weight percentages may be based on the solids content of the gypsum slurry. Moreover, the aforementioned weight percentages may be based on the weight of the stucco in the gypsum slurry. Additionally, the aforementioned weight percentages may be based on the weight of the gypsum in the gypsum core. In yet another embodiment, the aforementioned weight percentages may be based on the weight of the gypsum in the respective gypsum core layer.

[0064] The foaming agent may be one generally utilized in the art. For instance, the foaming agent may include an alkyl sulfate, an alkyl ether sulfate, or a mixture thereof. In one embodiment, the foaming agent includes an alkyl sulfate. In another embodiment, the foaming agent includes an alkyl ether sulfate. In a further embodiment, the foaming agent includes an alkyl sulfate without an alkyl ether sulfate. In an even further embodiment, the foaming agent includes a mixture of an alkyl sulfate and an alkyl ether sulfate. When a mixture is present, the alkyl ether sulfate may be present in an amount of 30 wt.% or less, such as 20 wt.% or less, such as 10 wt.% or less, such as 9 wt.% or less, such as 8 wt.% or less, such as 7 wt.% or less, such as 6 wt.% or less, such as 5 wt.% or less, such as 4 wt.% or less, such as 3 wt.% or less, such as 2 wt.% or less based on the combined weight of the alkyl sulfate and the alkyl ether sulfate. In addition, the alkyl ether sulfate may be present in an amount of 0.01 wt.% or more, such as 0.1 wt.% or more, such as 0.2 wt.% or more, such as 0.3 wt.% or more, such as 0.5 wt.% or more, such as 1 wt.% or more, such as 1.5 wt.% or more, such as 2 wt.% or more, such as 2.5 wt.% or more, such as 3 wt.% or more, such as 4Atty. Docket No.: NGCGB-139 wt.% or more, such as 5 wt.% or more, such as 10 wt.% or more, such as 20 wt.% or more, based on the combined weight of the alkyl sulfate and the alkyl ether sulfate.

[0065] As indicated, the foaming agent may include a combination of an alkyl sulfate and an alkyl ether sulfate. In this regard, the weight ratio of the alkyl sulfate to the alkyl ether sulfate may be 2 or more, such as 4 or more, such as 5 or more, such as 10 or more, such as 15 or more, such as 20 or more, such as 25 or more, such as 30 or more, such as 40 or more, such as 50 or more, such as 60 or more, such as 70 or more, such as 80 or more, such as 90 or more, such as 95 or more. The weight ratio may be less than 100, such as 99 or less, such as 98 or less, such as 95 or less, such as 90 or less, such as 85 or less, such as 80 or less, such as 75 or less, such as 70 or less, such as 60 or less, such as 50 or less, such as 40 or less, such as 30 or less, such as 20 or less, such as 15 or less, such as 10 or less, such as 8 or less, such as 5 or less, such as 4 or less.

[0066] In another aspect, the alkyl ether sulfate may be present in the foaming agent in an amount of 100 wt.% or less, such as 90 wt.% or less, such as 80 wt.% or less, such as 70 wt.% or less, such as 60 wt.% or less, such as 50 wt.% or less, such as 40 wt.% or less, such as 30 wt.% or less, such as 20 wt.% or less, such as 10 wt.% or less, such as 5 wt.% or less. The alkyl ether sulfate may be present in the foaming agent in an amount of 0.01 wt.% or more, such as 5 wt.% or more, such as 10 wt.% or more, such as 20 wt.% or more, such as 30 wt.% or more, such as 40 wt.% or more, such as 50 wt.% or more, such as 60 wt.% or more, such as 70 wt.% or more, such as 80 wt.% or more, such as 90 wt.% or more.

[0067] Additionally, in one aspect, the alkyl sulfate may be present in the foaming agent in an amount of 100 wt.% or less, such as 90 wt.% or less, such as 80 wt.% or less, such as 70 wt.% or less, such as 60 wt.% or less, such as 50 wt.% or less, such as 40 wt.% or less, such as 30 wt.% or less, such as 20 wt.% or less, such as 10 wt.% or less, such as 5 wt.% or less. The alkyl sulfate may be present in the foaming agent in an amount of 0.01 wt.% or more, such as 5 wt.% or more, such as 10 wt.% or more, such as 20 wt.% or more, such as 30 wt.% or more, such as 40 wt.% or more, such as 50 wt.% or more, such as 60 wt.% or more, such as 70 wt.% or more, such as 80 wt.% or more, such as 90 wt.% or more.Atty. Docket No.: NGCGB-139

[0068] In one aspect, the foaming agent may include one or more foam stabilizers, such as ethoxylated glycerin. The one or more foam stabilizers may be present in the gypsum slurry and / or gypsum core in an amount of 100 wt.% or less, such as 90 wt.% or less, such as 80 wt.% or less, such as 70 wt.% or less, such as 60 wt.% or less, such as 50 wt.% or less, such as 40 wt.% or less, such as 30 wt.% or less, such as 20 wt.% or less, such as 10 wt.% or less, such as 5 wt.% or less by weight of the foaming agent. The one or more foam stabilizers may be present in the gypsum slurry and / or gypsum core in an amount of 0.01 wt.% or more, such as 5 wt.% or more, such as 10 wt.% or more, such as 20 wt.% or more, such as 30 wt.% or more, such as 40 wt.% or more, such as 50 wt.% or more, such as 60 wt.% or more, such as 70 wt.% or more, such as 80 wt.% or more, such as 90 wt.% or more by weight of the foaming agent.

[0069] By utilizing a soap, foaming agent, and / or foam as disclosed herein, the gypsum slurry may include bubbles or voids having a particular size. Such size may then contribute to the void structure in the gypsum panel and the resulting properties. In this regard, the gypsum slurry may have bubbles or voids having a median size of 50 microns or more, such as 100 microns or more, such as 200 microns or more, such as 300 microns or more, such as 400 microns or more, such as 500 microns or more, such as 600 microns or more, such as 700 microns or more, such as 800 microns or more, such as 900 microns or more, such as 1,000 microns or more. The gypsum slurry may have bubbles or voids having a median size of 1,400 microns or less, such as 1,300 microns or less, such as 1,200 microns or less, such as 1,100 microns or less, such as 1,000 microns or less, such as 900 microns or less, such as 800 microns or less, such as 700 microns or less, such as 600 microns or less, such as 500 microns or less, such as 400 microns or less, such as 300 microns or less, such as 200 microns or less, such as 100 microns or less. Furthermore, while the aforementioned references a median size, it should be understood that in another embodiment, such size may also refer to an average size.

[0070] In one aspect, the foam may be provided in an amount of 75 lbs / MSF or more, such as 100 lbs / MSF or more, such as 125 lbs / MSF or more, such as 150 lbs / MSF or more, such as 175 lbs / MSF or more, such as 200 lbs / MSF or more, such as 225 lbs / MSF or more, such as 250 lbs / MSF or more, such as 275 lbs / MSF or more,Atty. Docket No.: NGCGB-139 such as 300 lbs / MSF or more, such as 325 lbs / MSF or more. The foam may be provided in an amount of 350 lbs / MSF or less, such as 325 lbs / MSF or less, such as 300 lbs / MSF or less, such as 275 lbs / MSF or less, such as 250 lbs / MSF or less, such as 225 lbs / MSF or less, such as 200 lbs / MSF or less, such as 175 lbs / MSF or less, such as 150 lbs / MSF or less, such as 125 lbs / MSF or less, such as 100 lbs / MSF or less.

[0071] The foam may comprise water and a foaming agent. In one aspect, the foaming agent may be provided in an amount of 0.05 lbs / MSF or more, such as 0.25 lbs / MSF or more, such as 0.5 lbs / MSF or more, such as 0.75 lbs / MSF or more, such as 1 lb / MSF or more, such as 2 lbs / MSF or more, such as 3 lbs / MSF or more, such as 4 lbs / MSF or more. The foaming agent may be provided in an amount of 5 lbs / MSF or less, such as 4 lbs / MSF or less, such as 3 lbs / MSF or less, such as 2 lbs / MSF or less, such as 1 lb / MSF or less, such as 0.5 lbs / MSF or less, such as 0.25 lbs / MSF or less. Further, in one aspect, the water utilized in the foam may be provided in an amount of 70 lbs / MSF or more, such as 75 lbs / MSF or more, such as 100 lbs / MSF or more, such as 125 lbs / MSF or more, such as 150 lbs / MSF or more, such as 175 lbs / MSF or more, such as 200 lbs / MSF or more, such as 225 lbs / MSF or more, such as 250 lbs / MSF or more, such as 275 lbs / MSF or more, such as 300 lbs / MSF or more, such as 325 lbs / MSF or more. The water utilized in the foam may be provided in an amount of 350 lbs / MSF or less, such as 325 lbs / MSF or less, such as 300 lbs / MSF or less, such as 275 lbs / MSF or less, such as 250 lbs / MSF or less, such as 225 lbs / MSF or less, such as 200 lbs / MSF or less, such as 175 lbs / MSF or less, such as 150 lbs / MSF or less, such as 125 lbs / MSF or less, such as 100 lbs / MSF or less.

[0072] In one aspect, the foaming agent may be provided in an amount of 0.5 lbs / ft3or more, such as 1 lb / ft3or more, such as 1.5 lbs / ft3or more, such as 2 lbs / ft3or more, such as 2.5 lbs / ft3or more, such as 3 lbs / ft3or more, such as 3.5 lbs / ft3or more, such as 4 lbs / ft3or more, such as 4.5 lbs / ft3or more, such as 5 lbs / ft3or more. The foaming agent may be provided in an amount of 25 lbs / ft3or less, such as 20 lbs / ft3or less, such as 15 lbs / ft3or less, such as 13 lbs / ft3or less, such as 11 lbs / ft3or less, such as 10 lbs / ft3or less, such as 9 lbs / ft3or less, such as 8 lbs / ft3or less, such as 7 lbs / ft3or less,Atty. Docket No.: NGCGB-139 such as 6 lbs / ft3or less. Notably, the aforementioned values may be based on the gypsum core.

[0073] In some aspects, the gypsum slurry and / or gypsum core may include a dispersant. The dispersant is not necessarily limited and may include any that can be utilized within the gypsum slurry. The dispersant may include carboxylates, sulfates, sulfonates, phosphates, mixtures thereof, etc.

[0074] In one embodiment, the dispersant may include a carboxylate, such as a carboxylate ether and in particular a polycarboxylate ether or a carboxylate ester and in particular a polycarboxylate ester.

[0075] In a further embodiment, the dispersant may include a sulfonate, such as a naphthalene sulfonate, a naphthalene sulfonate formaldehyde condensate, a sodium naphthalene sulfonate formaldehyde condensate, a lignosulfonate, a melamine formaldehyde condensate, or a mixture thereof.

[0076] In another embodiment, the dispersant may include a phosphate. For instance, the phosphate dispersant may be a polyphosphate dispersant, such as sodium trimetaphosphate, sodium tripolyphosphate, potassium tripolyphosphate, tetrasodium pyrophosphate, tetrapotassium pyrophosphate, tetrapotassium pyrophosphate, or a mixture thereof. In one embodiment, the polyphosphate dispersant may be sodium trimetaphosphate. In one embodiment, the phosphate may be sodium monofluorophosphate.

[0077] In this regard, the dispersant may include a sulfonate, a polycarboxylate ether, a polycarboxylate ester, or a mixture thereof. In one embodiment, the dispersant may include a sulfonate. In another embodiment, the dispersant may include a polycarboxylate ether. In a further embodiment, the dispersant may include a polycarboxylate ester.

[0078] In one aspect, the dispersant may be provided in an amount of 0.01 lbs / MSF or more, such as 0.5 lbs / MSF or more, such as 1 lb / MSF or more, such as 2 lbs / MSF or more, such as 5 lbs / MSF or more, such as 8 lbs / MSF or more, such as 10 lbs / MSF or more, such as 15 lbs / MSF or more, such as 20 lbs / MSF or more, such as 25 lbs / MSF or more, such as 30 lbs / MSF or more, such as 35 lbs / MSF or more. The dispersant may be provided in an amount of 40 lbs / MSF or less, such as 35 lbs / MSF or less, such as 30Atty. Docket No.: NGCGB-139 lbs / MSF or less, such as 25 lbs / MSF or less, such as 20 lbs / MSF or less, such as 15 lbs / MSF or less, such as 10 lbs / MSF or less, such as 8 lbs / MSF or less, such as 5 lbs / MSF or less, such as 2 lbs / MSF or less, such as 1 lb / MSF or less.

[0079] In one aspect, the dispersant may be provided in an amount of 0.5 lbs / ft3or more, such as 1 lb / ft3or more, such as 1.5 lbs / ft3or more, such as 2 lbs / ft3or more, such as 2.5 lbs / ft3or more, such as 3 lbs / ft3or more, such as 3.5 lbs / ft3or more, such as 4 lbs / ft3or more, such as 4.5 lbs / ft3or more, such as 5 lbs / ft3or more. The dispersant may be provided in an amount of 25 lbs / ft3or less, such as 20 lbs / ft3or less, such as 15 lbs / ft3or less, such as 13 lbs / ft3or less, such as 11 lbs / ft3or less, such as 10 lbs / ft3or less, such as 9 lbs / ft3or less, such as 8 lbs / ft3or less, such as 7 lbs / ft3or less, such as 6 lbs / ft3or less. Notably, the aforementioned values may be based on the gypsum core.

[0080] In some aspects, the gypsum slurry and / or gypsum core may include one or more surfactants. In general, the surfactant may be an anionic surfactant, a cationic surfactant, a non-ionic surfactant, a fluorinated surfactant, a silicon surfactant, or a mixture thereof. Generally, a surfactant may be in the form of a solid, a liquid, or a combination thereof.

[0081] As indicated above, in one embodiment, the surfactant may include an anionic surfactant. In general, anionic surfactants include those having one or more negatively charged functional groups. For instance, the anionic surfactant may include an alkali metal or ammonium salts of alkyl, aryl or alkylaryl sulfonates, sulfates, or a mixture thereof. In some aspects, the anionic surfactant may include ammonium lauryl sulfate, sodium lauryl sulfate, sodium octylphenol glycolether sulfate, sodium laureth sulfate, sodium myreth sulfate, sodium dodecylbenzene sulfonate, perfluorobutane sulfonate, dodecyl benzene sulfonate, alpha-olefin sulfonate, sodium lauryldiglycol sulfate, ammonium tritertiarybutyl phenol and penta- and octa-glycol sulfonates, sulfosuccinate salts such as disodium ethoxylated nonylphenol half ester of sulfosuccinic acid, disodium n-octyldecyl sulfosuccinate, sodium dioctyl sulfosuccinate, alpha olefin sulfonate and / or olefin sulfonate (e.g., sodium olefin sulfonates, such as sodium C14-C16olefin sulfonate, sodium C14-C18olefin sulfonate, and sodium C16-C18olefin sulfonate), and mixtures thereof. Other examples include a C8-C22 alkyl fatty acidAtty. Docket No.: NGCGB-139 salt of an alkali metal, alkaline earth metal, ammonium, alkyl substituted ammonium, for example, isopropylamine salt, or alkanolammonium salt, a C8-C22 alkyl fatty acid ester, a C8-C22alkyl fatty acid ester salt, and alkyl ether carboxylates. Further, the anionic surfactant may include a phosphate (alkyl-aryl ether phosphates, alkyl ether phosphates, etc.), a phosphite, a phosphonate, a carboxylate (e.g., sodium stearate, etc.), or a mixture thereof.

[0082] In one particular embodiment, the anionic surfactant may include a water- soluble salt, particularly an alkali metal salt, of an organic sulfur reaction product having in their molecular structure an alkyl radical containing from about 8 to 22 carbon atoms and a radical selected from the group consisting of sulfonic and sulfuric acid ester radicals. Organic sulfur based anionic surfactants include the salts of C10-C16 alkylbenzene sulfonates, C10-C22 alkane sulfonates, C10-C22 alkyl ether sulfates, C10-C22 alkyl sulfates, C4-C10dialkylsulfosuccinates, C10-C22acyl isothionates, alkyl diphenyloxide sulfonates, alkyl naphthalene sulfonates, C10-C20 alpha olefin sulfonates, and 2-acetamido hexadecane sulfonates. In one aspect, the anionic surfactant may include C6-C12linear and / or branched alkyl sulfates and / or C6-C12linear and / or branched alkyl ether sulfates. Organic phosphate based anionic surfactants include organic phosphate esters such as complex mono- or diester phosphates of hydroxyl- terminated alkoxide condensates, or salts thereof. Included in the organic phosphate esters are phosphate ester derivatives of polyoxyalkylated alkylaryl phosphate esters, of ethoxylated linear alcohols and ethoxylates of phenol. Particular examples of anionic surfactants include a polyoxyethylene alkyl ether sulfuric ester salt, a polyoxyethylene alkylphenyl ether sulfuric ester salt, polyoxyethylene styrenated alkylether ammonium sulfate, polyoxymethylene alkylphenyl ether ammonium sulfate, and the like, and mixtures thereof. For instance, the anionic surfactant may include a polyoxyethylene alkyl ether sulfuric ester salt, a polyoxyethylene alkylphenyl ether sulfuric ester salt, or a mixture thereof. In some aspects, the anionic surfactant may include sulfated alkanolamide, glyceride sulfate, or a mixture thereof.

[0083] As indicated above, in one embodiment, the surfactant may include a non- ionic surfactant. In one aspect, the nonionic surfactant may be an amine oxide. In one aspect, the nonionic surfactant may be an ethoxylate. For instance, the nonionicAtty. Docket No.: NGCGB-139 surfactant may be an ethoxylated fatty alcohol, a linear alcohol ethoxylate (e.g., narrow- range ethoxylate, octaethylene glycol monododecyl ether, pentaethylene glycol monododecyl ether, etc.), an alkylphenol ethoxylate (e.g., a nonoxynol, octylphenol ethoxylate, etc.), a fatty acid ethoxylate, an ethoxylated fatty ester, or an ethoxylated amine. In some aspects, the nonionic surfactant may be and / or include fatty acid amides (e.g., polyethoxylated tallow amine, cocamide monoethanolamine, cocamide diethanolamine, etc.), fatty acid esters of glycerol (e.g., glycerol monostearate, glyercol monolaurate, etc.), fatty acid esters of sorbitol (e.g., sorbitan monolaurate, sorbitan monostearate, sorbitan tristearate, etc.), alkyl polyglycosides (e.g., decyl glucoside, lauryl glucoside, octyl glucoside, etc.), block copolymers of polyethylene glycol and polypropylene glycol, glycerol alkyl esters, alkyl polyglucosides, polyoxyethylene glycol octylphenol ethers, sorbitan alkyl esters, polyoxyethylene glycol sorbitan alkyl esters, and mixtures thereof. For instance, the non-ionic surfactant may include a polyethylene oxide condensate of an alkyl phenol (e.g., the condensation product of an alkyl phenol having an alkyl group containing from 6 to 12 carbon atoms in either a straight chain or branched chain configuration, with ethylene oxide (e.g., present in amounts equal to 1 to 40 moles)). The alkyl substituent may be derived, for example, from polymerized propylene, di-isobutylene, octane or nonene. Other examples include dodecylphenol condensed with 12 moles of ethylene oxide per mole of phenol; dinonylphenol condensed with 5 moles of ethylene oxide per mole of phenol; nonylphenol condensed with 9 moles of ethylene oxide per mole of nonylphenol and di-iso-octylphenol condensed with 5 moles of ethylene oxide. The non-ionic surfactant may be a condensation product of a primary or secondary aliphatic alcohol having from 8 to 24 carbon atoms, in either straight chain or branched chain configuration, with from 1 to about 40 moles of alkylene oxide per mole of alcohol. The non-ionic surfactant may include a compound formed by condensing ethylene oxide with a hydrophobic base formed by the condensation of propylene oxide with propylene glycol (e.g., Pluronics). In one embodiment, the surfactant may be a silicon surfactant such as a polyether- modified siloxane.

[0084] In some aspects, a surfactant may include an ethoxylated alcohol that may include carbon chain lengths ranging from 12 to 20 carbon atoms. For instance, anAtty. Docket No.: NGCGB-139 ethoxylated alcohol may include carbon chain lengths ranging from 12 to 20 carbon atoms. A surfactant may include a blend of ethoxylated alcohols that have carbon chain lengths ranging from 12 to 20 carbon atoms. For instance, surfactant may include a blend of ethoxylated alcohols having carbon chain lengths ranging from 12 to 20 carbon atoms.

[0085] In one embodiment, the surfactant may include a cationic surfactant. For instance, the surfactant may include a cationic surfactant such as water-soluble quaternary ammonium compounds, polyammonium salts, a polyoxyethylene alkylamine and the like. In some aspects, the surfactant may include a cationic surfactant such as a quaternary ammonium salt (e.g., cetrimonium bromide, cetylpyridinium chloride, benzalkonium chloride, benzethonium chloride, dimethyldioctadecylammonium chloride, and dioctadecyldimethylammonium bromide, etc.).

[0086] Notably, the additives of the gypsum slurry and / or gypsum core may include a starch. The starch may be one generally utilized in the art. Such starch may be combined with the stucco and water. In this regard, such starch may be present in the gypsum slurry as well as the resulting gypsum core and gypsum panel. In one aspect, one or more components of a gypsum panel may be free of starch. For instance, the gypsum core and / or gypsum slurry may be free of starch. In one aspect, a gypsum panel formed in accordance with the present disclosure may be free of starch.

[0087] The starch may be a corn starch, a wheat starch, a milo starch, a potato starch, a rice starch, an oat starch, a barley starch, a cassava starch, a tapioca starch, a pea starch, a rye starch, an amaranth starch, or other commercially available starch. For example, in one embodiment, the starch may be a corn starch. In another embodiment, the starch may be a wheat starch. In an even further embodiment, the starch may be a milo starch.

[0088] Furthermore, the starch may be an unmodified starch or a modified starch. In one embodiment, the starch may be a modified starch. In another embodiment, the starch may be an unmodified starch. In an even further embodiment, the starch may be a mixture of a modified starch and an unmodified starch.

[0089] As indicated above, in one embodiment, the starch may be an unmodified starch. For instance, the starch may be a pearl starch (e.g., an unmodified corn starch).Atty. Docket No.: NGCGB-139 In addition, in one embodiment, the starch may also be a non-migrating starch. Also, with respect to gelatinization, the starch may be a non-pregelatinized starch.

[0090] As also indicated above, in another embodiment, the starch may be a modified starch. Such modification may be any as typically known in the art and is not necessarily limited. For instance, the modification may be via a physical, enzymatic, or chemical treatment. In one embodiment, the modification may be via a physical treatment. In another embodiment, the modification may be via an enzymatic treatment. In a further embodiment, the modification may be via a chemical treatment. The starch may be treated using many types of reagents. For example, the modification can be conducted using various chemicals, such as inorganic acids (e.g., hydrochloric acid, phosphorous acid or salts thereof, etc.), peroxides (e.g., sodium peroxide, potassium peroxide, hydrogen peroxide, etc.), anhydrides (e.g., acetic anhydride), etc. to break down the starch molecule.

[0091] In this regard, in one embodiment, the starch may be a pregelatinized starch, an acid-modified (or hydrolyzed) starch, an extruded starch, an oxidized starch, an oxyhydrolyzed starch, an ethoxylated starch, an ethylated starch, an acetylated starch, a mixture thereof, etc. For example, in one embodiment, the starch may be a pregelatinized starch. In another embodiment, the starch may be an acid-modified (or hydrolyzed) starch. In a further embodiment, the starch may be an extruded starch. In another embodiment, the starch may be an oxidized starch. In a further embodiment, the starch may be an oxyhydrolyzed starch. In another further embodiment, the starch may be an ethoxylated starch. In another embodiment, the starch may be an ethylated starch. In a further embodiment, the starch may be an acetylated starch.

[0092] In one embodiment, the starch may be a pregelatinized starch. In this regard, the starch may have been exposed to water and heat for breaking down a certain degree of intermolecular bonds within the starch. As an example and without intending to be limited by theory, during heating, water is absorbed into the amorphous regions of the starch thereby allowing it to swell. Then amylose chains may begin to dissolve resulting in a decrease in the crystallinity and an increase in the amorphous form of the starch.Atty. Docket No.: NGCGB-139

[0093] In another embodiment, the starch may be an acid-modified starch. Such acid modification can be conducted using various chemicals, such as inorganic acids (e.g., hydrochloric acid, phosphorous acid or salts thereof, etc.) to break down the starch molecule. Furthermore, by utilizing acid-modification, the starch may result in a low thinned starch, a medium thinned starch, or a high thinned starch. For example, a higher degree of modification can result in a lower viscosity starch while a lower degree of modification can result in a higher viscosity starch. The degree of modification and resulting viscosity may also affect the degree of migration of the starch. For instance, when presented within the core of the gypsum panel, a higher degree of modification and lower viscosity may provide a high migrating starch while a lower degree of modification and higher viscosity may provide a low migrating starch.

[0094] The starch may also have a particular gelling temperature. Without intending to be limited, this temperature is the point at which the intermolecular bonds of the starch are broken down in the presence of water and heat allowing the hydrogen bonding sites to engage more water. In this regard, the gelling temperature may be 60°C or more, such as 80°C or more, such as 100°C or more. The gelling temperature may be 120°C or less, such as 100°C or less, such as 80°C or less. In one embodiment, the aforementioned may refer to a peak gelling temperature.

[0095] As indicated above, the starch may have a particular gelling temperature. Without intending to be limited by theory, acid modification may provide a starch having a relatively lower gelling temperature. Meanwhile, without intending to be limited by theory, modifications of the hydroxyl group, such as by replacement via ethoxylation, ethylation, oxidation, or acetylation may provide a relatively lower gelling temperature or a reduction in gelling temperature. In this regard, in some embodiments, the starch may be acid-modified and chemically modified wherein the hydroxyl groups are substituted.

[0096] In one embodiment, the starch may be an extruded starch. For example, the extrusion may provide a thermomechanical process that can break the intermolecular bonds of the starch. Such extrusion may result in the gelatinization of starch due to an increase in the water absorption.

[0097] In another embodiment, the starch may be an oxidized starch. For example, the starch may be oxidized using various means known in the art. This may include, butAtty. Docket No.: NGCGB-139 is not limited to, chemical treatments utilizing oxidizing agents such as chlorites, chlorates, perchlorates, hypochlorites (e.g., sodium hypochlorite, etc.), peroxides (e.g., sodium peroxide, potassium peroxide, hydrogen peroxide, etc.), etc. In general, during oxidation, the molecules are broken down yielding a starch with a decreased molecular weight and a reduction in viscosity.

[0098] Also, it should be understood that the starch may include a combination of starches, such as any of those mentioned above. For instance, it should be understood that the starch may include more than one different starch. In addition, any combination of modifications may also be utilized to form the starch utilized according to the present invention.

[0099] In one aspect, the starch may be present in an amount of 0.001 lbs / MSF or more, such as 0.01 lbs / MSF or more, such as 0.05 lbs / MSF or more, such as 0.1 lbs / MSF or more, such as 0.2 lbs / MSF or more, such as 0.25 lbs / MSF or more, such as 0.5 lbs / MSF or more, such as 0.75 lbs / MSF or more, such as 1 lb / MSF or more, such as 1.5 lbs / MSF or more, such as 2 lbs / MSF or more, such as 2.5 lbs / MSF or more, such as 3 lbs / MSF or more, such as 4 lbs / MSF or more, such as 5 lbs / MSF or more, such as 8 lbs / MSF or more, such as 10 lbs / MSF or more, such as 15 lbs / MSF or more, such as 20 lbs / MSF or more. The starch may be present in an amount of 50 lbs / MSF or less, such as 30 lbs / MSF or less, such as 25 lbs / MSF or less, such as 20 lbs / MSF or less, such as 15 lbs / MSF or less, such as 10 lbs / MSF or less, such as 5 lbs / MSF or less, such as 4 lbs / MSF or less, such as 3 lbs / MSF or less, such as 2.5 lbs / MSF or less, such as 2 lbs / MSF or less, such as 1.5 lbs / MSF or less, such as 1 lb / MSF or less.

[0100] The manner in which the components (e.g., stucco, gypsum, water) for the gypsum slurry are combined is not necessarily limited. For instance, the gypsum slurry can be made using any method or device generally known in the art. In particular, the components of the slurry can be mixed or combined using any method or device generally known in the art. For instance, the components of the gypsum slurry may be combined in any type of device, such as a mixer and in particular a pin mixer or pinless mixer. In this regard, the manner in which the components are incorporated into the gypsum slurry is not necessarily limited by the present invention. Such components may be provided prior to a mixing device, directly into a mixing device, in a separateAtty. Docket No.: NGCGB-139 mixing device, and / or even after the mixing device. For instance, the respective components may be provided prior to a mixing device. In another embodiment, the respective components may be provided directly into a mixing device. For instance, in one embodiment, the foaming agent or soap may be provided directly into the mixer. Alternatively, the respective components may be provided after the mixing device (such as to the canister or boot, using a secondary mixer, or applied directly onto the slurry after a mixing device) and may be added directly or as part of a mixture. Whether provided prior to, into, or after the mixing device, the components may be combined directly with another component of the gypsum slurry. In addition, whether providing the components prior to or after the mixing device or directly into the mixing device, the compound may be delivered as a solid, as a dispersion / solution, or a combination thereof.

[0101] Upon deposition of the gypsum slurry, the calcium sulfate hemihydrate reacts with the water to hydrate the calcium sulfate hemihydrate into a crystalline matrix of calcium sulfate dihydrate. In this respect, the stucco may convert into calcium sulfate dihydrate. Such reaction may allow for the gypsum to set and become firm thereby allowing for the panels to be cut at the desired length. In this regard, the method may comprise a step of reacting calcium sulfate hemihydrate with water to form calcium sulfate dihydrate or allowing the calcium sulfate hemihydrate to hydrate to calcium sulfate dihydrate. In this regard, the method may allow for the slurry to set to form a gypsum panel. In addition, during this process, the method may allow for drying of the gypsum slurry, in particular drying any free water instead of combined water of the gypsum slurry. Such drying may occur prior to the removal of any free moisture or water in a heating or drying device after a cutting step. Thereafter, the method may also comprise a step of cutting a continuous gypsum sheet into a gypsum panel. Then, after the cutting step, the method may comprise a step of supplying the gypsum panel to a heating or drying device to undergo a drying process. For instance, such a heating or drying device may be a kiln and may allow for removal (e.g., evaporation) of any free water. The temperature and time required for drying in a heating device is not necessarily limited by the present invention.Atty. Docket No.: NGCGB-139

[0102] In one embodiment, the gypsum core may include a first gypsum core layer and a second gypsum core layer. The first gypsum core layer may be between the first facing material (e.g., front of the gypsum panel) and the second gypsum core layer. In addition, the first gypsum core layer may have a density greater than the second gypsum core layer. Accordingly, the first gypsum core layer may be formed using a gypsum slurry without the use of foam and / or a foaming agent or with a reduced amount of foam and / or a foaming agent, which may be utilized in forming the second gypsum core layer. In this regard, in one embodiment, the first gypsum core layer may have the same composition as the second gypsum core layer except that the second gypsum core layer may be formed using foam and / or a foaming agent or a greater amount of foam and / or a foaming agent.

[0103] In one embodiment, the gypsum core may also include a third gypsum core layer. The third gypsum core layer may be provided between the second gypsum core layer and a second facing material (e.g., back of the gypsum panel). Like the first gypsum core layer, the third gypsum core layer may also be a dense gypsum core layer. In particular, the third gypsum core layer may have a density greater than the second gypsum core layer. Accordingly, the third gypsum core layer may be formed using a gypsum slurry without the use of foam and / or a foaming agent or with a reduced amount of foam and / or a foaming agent, which may be utilized in forming the second gypsum core layer. In this regard, in one embodiment, the third gypsum core layer may have the same composition as the second gypsum core layer except that the second gypsum core layer may be formed using foam and / or a foaming agent or a greater amount of foam and / or a foaming agent.

[0104] When the gypsum core includes multiple gypsum core layers, the gypsum slurry may be deposited in multiple steps for forming the gypsum core. For instance, each gypsum core layer may require a separate deposition of gypsum slurry. In this regard, with a first gypsum core layer and a second gypsum core layer, a first gypsum slurry may be deposited followed by a second gypsum slurry. The first gypsum slurry and the second gypsum slurry may have the same composition except that the second gypsum slurry may include foam and / or a foaming agent or more foam and / or a foaming agent than the first gypsum slurry. In this regard, in one embodiment, the first gypsumAtty. Docket No.: NGCGB-139 slurry may not include foam and / or a foaming agent. Accordingly, the first gypsum slurry may result in a dense gypsum core layer, in particular a non-foamed gypsum core layer. Such gypsum core layer may have a density greater than the gypsum core layer formed from the second gypsum slurry, or foamed gypsum core layer.

[0105] Similarly, when the gypsum core includes three gypsum core layers, the gypsum slurry may be deposited in three steps for forming the gypsum core. For example, a first and second gypsum slurry may be deposited as indicated above and a third gypsum slurry may be deposited onto the second gypsum slurry. The third gypsum slurry and the second gypsum slurry may have the same composition except that the second gypsum slurry may include foam and / or a foaming agent or more foam and / or a foaming agent than the third gypsum slurry. In this regard, in one embodiment, the third gypsum slurry may not include foam and / or a foaming agent. Accordingly, the third gypsum slurry may result in a dense gypsum core layer, in particular a non-foamed gypsum core layer. Such gypsum core layer may have a density greater than the gypsum core layer formed from the second gypsum slurry, or foamed gypsum core layer.

[0106] The first gypsum core layer may have a thickness that is 0.5% or more, such as 1% or more, such as 2% or more, such as 3% or more, such as 4% or more, such as 5% or more, such as 10% or more, such as 15% or more than the thickness of the second (or foamed) gypsum core layer. The thickness may be 80% or less, such as 60% or less, such as 50% or less, such as 40% or less, such as 30% or less, such as 25% or less, such as 20% or less, such as 15% or less, such as 10% or less, such as 8% or less, such as 5% or less the thickness of the second (or foamed) gypsum core layer. In one embodiment, such relationship may also be between the third gypsum core layer and the second gypsum core layer.

[0107] The density of the second (or foamed) gypsum core layer may be 0.5% or more, such as 1% or more, such as 2% or more, such as 3% or more, such as 4% or more, such as 5% or more, such as 10% or more, such as 15% or more the density of the first (or non-foamed) gypsum core layer. The density of the second (or foamed) gypsum core layer may be 80% or less, such as 60% or less, such as 50% or less, such as 40% or less, such as 30% or less, such as 25% or less, such as 20% or less, suchAtty. Docket No.: NGCGB-139 as 15% or less, such as 10% or less, such as 8% or less, such as 5% or less the density of the first (or non-foamed) gypsum core layer. In one embodiment, such relationship may also be between the third gypsum core layer and the second gypsum core layer. In addition, in one embodiment, all of the gypsum core layers may have a different density.

[0108] The present disclosure is also directed to a method of forming and / or constructing a wallboard assembly. The method may comprise forming or providing a first wallboard, such as a gypsum panel in accordance with the present disclosure. The method may comprise providing an installed wallboard (e.g., a second wallboard) attached to a building wall or ceiling. The method may also include a further step of attaching, fastening, and / or affixing the first wallboard (e.g., a gypsum panel) to the installed or existing wallboard.

[0109] The gypsum panel disclosed herein may have many applications. For instance, the gypsum panel may be used as a standalone panel in construction for the preparation of walls, ceilings, floors, roofs, etc. As used in the present disclosure, the term “gypsum panel,” generally refers to any panel, sheet, or planar structure, either uniform or formed by connected portions or pieces, that is constructed to at least partially establish one or more physical boundaries. Such existing, installed, or otherwise established or installed wall or ceiling structures comprise materials that may include, as non-limiting examples, gypsum, stone, ceramic, cement, wood, composite, or metal materials. The installed gypsum panel forms part of a building structure, such as a wall or ceiling.

[0110] In one embodiment, the gypsum panel may be processed such that any respective gypsum core layer may have an average void size of about 50 microns to about 1200 microns, such as about 50 microns or more, such as about 100 microns or more, such as about 150 microns or more, such as about 200 microns or more, such as about 250 microns or more, such as about 300 microns or more, such as about 350 microns or more, such as about 400 microns or more, such as about 450 microns or more, such as about 500 microns or more, such as about 600 microns or more, such as about 700 microns or more, such as about 800 microns or more. Generally, the average void size may be about 1200 microns or less, such as about 1100 microns orAtty. Docket No.: NGCGB-139 less, such as about 1000 microns or less, such as about 900 microns or less, such as about 800 microns or less, such as about 700 microns or less, such as about 600 microns or less, such as about 500 microns or less, such as about 400 microns or less, such as about 300 microns or less, such as about 200 microns or less, such as about 100 microns or less. In one embodiment, such core voids may reference any air voids due to voids generated from the use of a soap / foam. Furthermore, while the aforementioned references an average void size, it should be understood that in another embodiment, such size may also refer to a median void size.

[0111] The specific surface area of the gypsum core is not necessarily limited and may be from about 0.25 m2 / g to about 15 m2 / g, including all increments of 0.01 m2 / g therebetween. For instance, the specific surface area may be 0.25 m2 / g or more, such as 0.5 m2 / g or more, such as 1 m2 / g or more, such as 1.5 m2 / g or more, such as 2 m2 / g or more, such as 2.5 m2 / g or more, such as 3 m2 / g or more, such as 3.5 m2 / g or more, such as 4 m2 / g or more, such as 5 m2 / g or more, such as 6 m2 / g or more, such as 8 m2 / g or more, such as 10 m2 / g or more. The specific surface area of the gypsum core may be 15 m2 / g or less, such as 10 m2 / g or less, such as 8 m2 / g or less, such as 6 m2 / g or less, such as 4 m2 / g or less, such as 3.5 m2 / g or less, such as 3 m2 / g or less, such as 2.5 m2 / g or less, such as 2 m2 / g or less, such as 1.5 m2 / g or less, such as 1 m2 / g or less.

[0112] The thickness of the gypsum panel, and in particular, the gypsum core, is not necessarily limited and may be from about 0.25 inches to about 1 inch. For instance, the thickness may be at least 1 / 4 inches, such as at least 5 / 16 inches, such as at least 3 / 8 inches, such as at least 1 / 2 inches, such as at least 5 / 8 inches, such as at least 3 / 4 inches, such as at least 1 inch. In this regard, the thickness may be about any one of the aforementioned values. For instance, the thickness may be about 1 / 4 inches. Alternatively, the thickness may be about 3 / 8 inches. In another embodiment, the thickness may be about 1 / 2 inches. In a further embodiment, the thickness may be about 5 / 8 inches. In another further embodiment, the thickness may be about 1 inch. In addition, at least two gypsum panels may be combined to create another gypsum panel, such as a composite gypsum panel. For example, at least two gypsum panels having a thickness of about 5 / 16 inches each may be combined or sandwiched to create aAtty. Docket No.: NGCGB-139 gypsum panel having a thickness of about 5 / 8 inches. While this is one example, it should be understood that any combination of gypsum panels may be utilized to prepare a sandwiched gypsum panel. With regard to the thickness, the term “about” may be defined as within 10%, such as within 5%, such as within 4%, such as within 3%, such as within 2%, such as within 1%. However, it should be understood that the present invention is not necessarily limited by the aforementioned thicknesses.

[0113] In addition, the panel weight of the gypsum panel is not necessarily limited. For instance, the gypsum panel may have a panel weight of 500 lbs / MSF or more, such as about 600 lbs / MSF or more, such as about 700 lbs / MSF or more, such as about 800 lbs / MSF or more, such as about 900 lbs / MSF or more, such as about 1000 lbs / MSF or more, such as about 1100 lbs / MSF or more, such as about 1200 lbs / MSF or more, such as about 1300 lbs / MSF or more, such as about 1400 lbs / MSF or more, such as about 1500 lbs / MSF or more, such as about 1600 lbs / MSF or more, such as about 1800 lbs / MSF or more, such as about 2000 lbs / MSF or more, such as about 2200 lbs / MSF or more, such as about 2400 lbs / MSF or more. The panel weight may be about 7000 lbs / MSF or less, such as about 6000 lbs / MSF or less, such as about 5000 lbs / MSF or less, such as about 4000 lbs / MSF or less, such as about 3000 lbs / MSF or less, such as about 2500 lbs / MSF or less, such as about 2000 lbs / MSF or less, such as about 1800 lbs / MSF or less, such as about 1600 lbs / MSF or less, such as about 1500 lbs / MSF or less, such as about 1400 lbs / MSF or less, such as about 1300 lbs / MSF or less, such as about 1200 lbs / MSF or less. Such panel weight may be a dry panel weight such as after the panel leaves the heating or drying device (e.g., kiln).

[0114] In addition, the gypsum panel may have a density of about 15 pcf or more, such as about 20 pcf or more, such as about 25 pcf or more, such as about 28 pcf or more, such as about 30 pcf or more, such as about 33 pcf or more, such as about 35 pcf or more, such as about 38 pcf or more, such as about 40 pcf or more, such as about 43 pcf or more, such as about 45 pcf or more, such as about 48 pcf or more. The panel may have a density of about 60 pcf or less, such as about 50 pcf or less, such as about 40 pcf or less, such as about 35 pcf or less, such as about 33 pcf or less, such as about 30 pcf or less, such as about 28 pcf or less, such as about 25 pcf or less, such as about 23 pcf or less, such as about 20 pcf or less, such as about 18 pcf or less.Atty. Docket No.: NGCGB-139

[0115] The gypsum panel may have a certain nail pull resistance, which generally is a measure of the force required to pull a gypsum panel off a wall by forcing a fastening nail through the panel. The values obtained from the nail pull test generally indicate the maximum stress achieved while the fastener head penetrates through the panel surface and core. In this regard, the gypsum panel exhibits a nail pull resistance of at least about 25 lbf, such as at least about 30 pounds, such as at least about 35 lbf, such as at least about 40 lbf, such as at least about 45 lbf, such as at least about 50 lbf, such as at least about 55 lbf, such as at least about 60 lbf, such as at least about 65 lbf, such as at least about 70 lbf, such as at least about 75 lbf, such as at least about 77 lbf, such as at least about 80 lbf, such as at least about 85 lbf, such as at least about 90 lbf, such as at least about 95 lbf, such as at least about 100 lbf as tested according to ASTM C1396- 17. The nail pull resistance may be about 400 lbf or less, such as about 300 lbf or less, such as about 200 lbfor less, such as about 150 lbfor less, such as about 140 lbfor less, such as about 130 lbf or less, such as about 120 lbf or less, such as about 110 lbf or less, such as about 105 lbf or less, such as about 100 lbf or less, such as about 95 lbf or less, such as about 90 lbfor less, such as about 85 lbfor less, such as about 80 lbfor less as tested according to ASTM C1396-17. Such nail pull resistance may be based upon the thickness of the gypsum panel. For instance, when conducting a test, such nail pull resistance values may vary depending on the thickness of the gypsum panel. As an example, the nail pull resistance values above may be for a 5 / 8 inch panel. However, it should be understood that instead of a 5 / 8 inch panel, such nail pull resistance values may be for any other thickness gypsum panel as mentioned herein.

[0116] The gypsum panel may have a certain compressive strength. For instance, the compressive strength may be about 150 psi or more, such as about 200 psi or more, such as about 250 psi or more, such as about 300 psi or more, such as about 350 psi or more, such as about 375 psi or more, such as about 400 psi or more, such as about 500 psi or more as tested according to ASTM C473-19. The compressive strength may be about 3000 psi or less, such as about 2500 psi or less, such as about 2000 psi or less, such as about 1700 psi or less, such as about 1500 psi or less, such as about 1300 psi or less, such as about 1100 psi or less, such as about 1000 psi or less, such as about 900 psi or less, such as about 800 psi or less, such as about 700Atty. Docket No.: NGCGB-139 psi or less, such as about 600 psi or less, such as about 500 psi or less. Such compressive strength may be based upon the density and thickness of the gypsum panel. For instance, when conducting a test, such compressive strength values may vary depending on the thickness of the gypsum panel. As an example, the compressive strength values above may be for a 5 / 8 inch panel. However, it should be understood that instead of a 5 / 8 inch panel, such compressive strength values may be for any other thickness gypsum panel as mentioned herein.

[0117] In addition, the gypsum panel may have a core hardness of at least about 8 lbf, such as at least about 10 lbf, such as at least about 11 lbf, such as at least about 12 lbf, such as at least about 15 lbf, such as at least about 18 lbf, such as at least about 20 lbf as tested according to ASTM C1396-17. The gypsum panel may have a core hardness of 50 lbf or less, such as about 40 lbf or less, such as about 35 lbf or less, such as about 30 lbfor less, such as about 25 lbfor less, such as about 20 lbfor less, such as about 18 lbf or less, such as about 15 lbf or less as tested according to ASTM C1396-17. In addition, the gypsum panel may have an end hardness according to the aforementioned values. Such core hardness may be based upon the thickness of the gypsum panel. For instance, when conducting a test, such core hardness values may vary depending on the thickness of the gypsum panel. As an example, the core hardness values above may be for a 5 / 8 inch panel. However, it should be understood that instead of a 5 / 8 inch panel, such core hardness values may be for any other thickness gypsum panel as mentioned herein.

[0118] In addition, the gypsum panel may have an edge hardness of at least about 8 lbf, such as at least about 10 lbf, such as at least about 11 lbf, such as at least about 12 lbf, such as at least about 15 lbf, such as at least about 18 lbf, such as at least about 20 lbf, such as at least about 24 lbf, such as at least about 28 lbf, such as at least about 30 lbf, such as at least about 33 lbfas tested according to ASTM C1396-17 and ASTM C473-19. The gypsum panel may have an edge hardness of about 50 lbfor less, such as about 40 lbf or less, such as about 35 lbf or less, such as about 30 lbf or less, such as about 25 lbfor less, such as about 20 lbfor less, such as about 18 lbfor less, such as about 15 lbfor less as tested according to ASTM C1396-17 and ASTM C473-19. Such edge hardness may be based upon the thickness of the gypsum panel. For instance,Atty. Docket No.: NGCGB-139 when conducting a test, such edge hardness values may vary depending on the thickness of the gypsum panel. As an example, the edge hardness values above may be for a 5 / 8 inch panel. However, it should be understood that instead of a 5 / 8 inch panel, such edge hardness values may be for any other thickness gypsum panel as mentioned herein.

[0119] In addition, it may also be desired to have an effective bond between the facing material and the gypsum core. Typically, a humidified bond test is performed for 2 hours in a humidity chamber at 90°F and 90% humidity. In this test, after exposure, the facing material is removed to determine how much remains on the gypsum panel. The percent coverage (or surface area) can be determined using various optical analytical techniques. In this regard, the facing material may cover 100% or less, such as less than 90%, such as less than 80%, such as less than 70%, such as less than 60%, such as less than 50%, such as less than 40%, such as less than 30%, such as less than 25%, such as less than 20%, such as less than 15%, such as less than 10%, such as less than 9%, such as less than 8% of the surface area of the gypsum core upon conducting the test. Such percentage may be for a face of the gypsum panel. Alternatively, such percentage may be for a back of the gypsum panel. Further, such percentages may apply to the face and the back of the gypsum panel. In addition, such values may be for an average of at least 3 gypsum panels, such as at least 5 gypsum panels.

[0120] Also, it may be desired to have a particular humidified deflection based on exposure in an atmosphere of 90°F ± 3°F and 90% ± 3% relative humidity for 48 hours. For instance, the humidified deflection may be 0.1 inches or less, such as 0.08 inches or less, such as 0.06 inches or less, such as 0.05 inches or less, such as 0.04 inches or less, such as 0.03 inches or less, such as 0.02 inches or less, such as 0.01 inches or less, such as 0.005 inches or less. The humified deflection may be 0 inches or more, such as 0.0001 inches or more, such as 0.0005 inches or more, such as 0.001 inches or more, such as 0.003 inches or more, such as 0.005 inches or more, such as 0.008 inches or more, such as 0.01 inches or more, such as 0.015 inches or more. Such values may be for an average of at least 3 gypsum panels.Atty. Docket No.: NGCGB-139 EXAMPLES Test Methods

[0121] Thermal Resistance: The thermal resistance was determined in accordance with ASTM C518-17. ASTM C518-17 is the standard test method for steady-state thermal transmission properties by means of a heat flow apparatus. The heat flow apparatus utilized was a LaserComp FOX 304 Heat Flow Meter. Prior to testing, the gypsum panel samples were placed in a conditioning room, with an atmosphere of 22 ± 2°C (72°F) and 50 ± 5% relative humidity, where they remained to condition to constant weight for approximately 96 hours. The test conditions were a mean temperature of 23.9°C [75°F] and a temperature differential across the gypsum panel sample of 22.2°C [40°F]. The gypsum panel sample size for each test was 16 mm x 305 mm x 305 mm [.63 in. x 12 in. x 12 in.].

[0122] Thermal Resistivity: The thermal resistivity was determined in accordance with ASTM C518-17. ASTM C518-17 is the standard test method for steady-state thermal transmission properties by means of a heat flow apparatus. The heat flow apparatus utilized can be a LaserComp FOX 304 Heat Flow Meter. Prior to testing, the gypsum panel samples were placed in a conditioning room, with an atmosphere of 22 ± 2°C (72°F) and 50 ± 5% relative humidity, where they remained to condition to constant weight for approximately 96 hours. The test conditions were a mean temperature of 23.9°C [75°F] and a temperature differential across the gypsum panel of 22.2°C [40°F]. The gypsum panel sample size for each test was 16 mm x 305 mm x 305 mm [.63 in. x 12 in. x 12 in.].

[0123] Apparent Thermal Conductivity: The apparent thermal conductivity was determined in accordance with ASTM C518-17. ASTM C518-17 is the standard test method for steady-state thermal transmission properties by means of a heat flow apparatus. The heat flow apparatus utilized can be a LaserComp FOX 304 Heat Flow Meter. Prior to testing, the gypsum panel samples were placed in a conditioning room, with an atmosphere of 22 ± 2°C (72°F) and 50 ± 5% relative humidity, where they remained to condition to constant weight for approximately 96 hours. The test conditions were a mean temperature of 23.9°C [75°F] and a temperature differentialAtty. Docket No.: NGCGB-139 across the gypsum panel of 22.2°C [40°F]. The gypsum panel sample size for each test was 16 mm x 305 mm x 305 mm [.63 in. x 12 in. x 12 in.]. Example 1

[0124] A gypsum panel sample was made using a 1 / 8” polyurethane foam layer positioned between two gypsum core layers. The gypsum panel sample had two paper facing materials. The gypsum panel sample weighed 1896 lbs / MSF. The thermal resistance, thermal resistivity, and apparent thermal conductivity of the gypsum panel sample were determined in accordance with the test methods above, which are in accordance with ASTM C518-17. Table 1 Description Result Metric US CustomaryExample 2

[0125] A gypsum panel sample was made using a 1 / 4” polyurethane foam layer positioned between two gypsum core layers. The gypsum panel sample had two paper facing materials. The gypsum panel sample weighed 1880 lbs / MSF. The thermal resistance, thermal resistivity, and apparent thermal conductivity of the gypsum panel sample were determined in accordance with the test methods above, which are in accordance with ASTM C518-17. Table 2 Description ResultAtty. Docket No.: NGCGB-139 Metric US Customary Specimen Thickness mm [in.] 16.30 [0.642]p

[0126] A gypsum panel sample was made using a 1 / 8” cork natural fiber material layer positioned between two gypsum core layers. The gypsum panel sample had two paper facing materials. The gypsum panel sample weighed 2394 lbs / MSF. The thermal resistance, thermal resistivity, and apparent thermal conductivity of the gypsum panel sample were determined in accordance with the test methods above, which are in accordance with ASTM C518-17. Table 3 Description Result Metric US CustomaryExample 4Atty. Docket No.: NGCGB-139

[0127] A gypsum panel sample was made using a 3 / 16” cork natural fiber material layer positioned between two gypsum core layers. The gypsum panel sample had two paper facing materials. The gypsum panel sample weighed 2050 lbs / MSF. The thermal resistance, thermal resistivity, and apparent thermal conductivity of the gypsum panel sample were determined in accordance with the test methods above, which are in accordance with ASTM C518-17. Table 4 Description Result Metric US Customary i Thi k

[0128] While particular embodiments of the present disclosure have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the present disclosure. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this disclosure.

Claims

Atty. Docket No.: NGCGB-139 CLAIMS 1. A gypsum panel comprising: a gypsum core comprising gypsum; and a first facing material and a second facing material, the first facing material, the second facing material, or both comprising a natural fiber material layer comprising plant-derived fibers in an amount of about 20 wt.% or more, the plant- derived fibers being derived from leaves, stems, bark, roots, seeds, fruits, stalks, branches, trunks, or a combination thereof of one or more plants.

2. The gypsum panel of claim 1, wherein the plant-derived fibers are derived from the bark of the one or more plants.

3. The gypsum panel of claim 1, wherein the plant-derived fibers are cork fibers.

4. The gypsum panel of claim 1, wherein the natural fiber material layer comprises plant-derived fibers in an amount of about 30 wt.% or more.

5. The gypsum panel of claim 1, wherein the natural fiber material layer comprises plant-derived fibers in an amount of about 40 wt.% or more.

6. The gypsum panel of claim 1, wherein the natural fiber material layer comprises plant-derived fibers in an amount of about 50 wt.% or more.

7. The gypsum panel of claim 1, wherein the natural fiber material layer has a thickness of about 1 inch or less.

8. The gypsum panel of claim 1, wherein the natural fiber material layer has a thickness of about 1 / 2 inch or less.

9. The gypsum panel of claim 1, wherein the gypsum panel has a thermal resistance of about 0.04 K-m2 / W or more as determined in accordance with ASTM C518-17.

10. The gypsum panel of claim 1, wherein the gypsum panel has a thermal resistivity of about 3.0 K-m / W or more as determined in accordance with ASTM C518- 17.

11. The gypsum panel of claim 1, wherein the gypsum panel has an apparent thermal conductivity of about 0.04 W / m-K or more as determined in accordance with ASTM C518-17.Atty. Docket No.: NGCGB-139 12. A gypsum panel comprising: a gypsum core comprising gypsum, the gypsum core being formed from a gypsum slurry, the gypsum core comprising two or more gypsum core layers; a first facing material and a second facing material; and a natural fiber material layer positioned between at least two of the two or more gypsum core layers, the natural fiber material layer comprising plant-derived fibers in an amount of about 20 wt.% or more, the plant-derived fibers being derived from leaves, stems, bark, roots, seeds, fruits, stalks, branches, trunks, or a combination thereof of one or more plants; wherein at least a portion of a thickness of the natural fiber material layer is penetrated by the gypsum slurry.

13. The gypsum panel of claim 12, wherein the plant-derived fibers are derived from the bark of the one or more plants.

14. The gypsum panel of claim 12, wherein the plant-derived fibers are cork fibers.

15. The gypsum panel of claim 12, wherein the natural fiber material layer comprises plant-derived fibers in an amount of about 50 wt.% or more.

16. The gypsum panel of claim 12, wherein the natural fiber material layer has a thickness of about 1 / 2 inch or less.

17. The gypsum panel of claim 12, wherein the gypsum panel has a thermal resistance of about 0.04 K-m2 / W or more as determined in accordance with ASTM C518-17.

18. The gypsum panel of claim 12, wherein the gypsum panel has a thermal resistivity of about 3.0 K-m / W or more as determined in accordance with ASTM C518- 17.

19. The gypsum panel of claim 12, wherein the gypsum panel has an apparent thermal conductivity of about 0.04 W / m-K or more as determined in accordance with ASTM C518-17.

20. A method for making a gypsum panel comprising: providing a first facing material;Atty. Docket No.: NGCGB-139 depositing a gypsum slurry comprising stucco and water onto the first facing material; providing a second facing material on the gypsum slurry; and allowing the stucco to convert to calcium sulfate dihydrate; wherein the gypsum panel comprises a natural fiber material layer, the natural fiber material layer comprising plant-derived fibers in an amount of about 20 wt.% or more, the plant-derived fibers being derived from leaves, stems, bark, roots, seeds, fruits, stalks, branches, trunks, or a combination thereof of one or more plants.

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