Abstract: A method of producing a composite core member along a production line is disclosed. The core member is designed to be used within a composite panel of a tractor trailer. The method comprises the steps of providing an intermediate core member comprising a reinforced material positioned on at least one end of the intermediate core member and producing at least two strips of reinforced material. The intermediate core member is inserted between the strips of reinforced material and the strips of reinforced material are coupled to a first side and a second side of the intermediate core member to form the core member.

Abstract: A gypsum composition, board, and method of producing a gypsum board with increased fire endurance are described. The set gypsum-containing composition can be used to prepare a gypsum board having fire endurance, based on particular water-to-stucco ratios.

Abstract: Membrane-ready fibrous faced gypsum panels, methods, and apparatus are provided. The panels include a first fibrous mat having a first surface and a second surface, a second fibrous mat having a first surface and a second surface, a gypsum core in contact with the second surfaces of the first and second fibrous mats, and a material coating that covers the first surface of the first fibrous mat and forms a substantially smooth outer surface.

Abstract: The present invention provides a gypsum composition, a gypsum board and their preparation method and the use of DHA as an anti-sagging additive in a gypsum product. Said gypsum board comprises set gypsum prepared from the composition; while said composition comprises gypsum, and an anti-deformation additive, wherein the anti-deformation additive comprises at least one selected from a group consisting of dehydroascorbic acid, dehydroascorbate and semidehydroascorbic acid. The set gypsum prepared from the said composition shows better anti-sagging or deformation resisting property. The gypsum product of the present invention is hardly distorted and has stronger stability even in the condition of high humidity, thus improve the quality of the gypsum product to meet the demands of the customer.

Abstract: A lightweight gypsum wallboard having a foamed gypsum core reinforced with pre-gelatinized, e.g., pre-gelled, starch and prepared by mixing an aqueous foam into a gypsum slurry comprising a source of calcined gypsum (commonly known as plaster of Paris), pre-gelled starch and a lignosulfonate dispersant; allowing the so-formed gypsum slurry to set, and then drying the set gypsum core.

Abstract: Disclosed are cementitious product, as well as cementitious slurry, and method of forming the product. To reduce density in the cementitious product, foam is included in the slurry and in the method of forming the product. The slurry includes cementitious particles, water, and air bubbles such as from compressed air. Instead of using detergent chemistry at the gas/water interface of bubbles, the present invention uses a surface modifying agent for the cementitious particles in the slurry. The modified particles act to produce stable foam in the slurry. As an example mode of introduction, the surface modifier can be added (e.g., as solid or solution) directly into a bulk cementitious slurry that forms the product. As another example, the surface modifier can be added in a separate solution with water, air bubbles, and cementitious particles that serve as additive to the main cementitious slurry, where the separate solution is then added to the main cementitious slurry.

Abstract: Disclosed is a method of preparing a mat-faced cementitious article composite. A mat-faced article (e.g., board) is formed and the composite is formed upon application of a finish composition (e.g., hydrophobic). In one aspect, the mat-faced gypsum article comprises a mat having an inner surface adjacent to a cementitious core first surface and an opposite outer mat surface. An aqueous cementitious finish composition is applied to the outside mat surface to form the mat-faced cementitious article composite. Desirably, the finish composite can suitably be applied by a roller assembly comprising a finish roller. In some embodiments, the finish roller has an uneven surface, including for example, grooves or depressions (e.g., circumferential or longitudinal) defined therein.

Abstract: The present invention provides an apparatus and a method for fractionating gypsum slurry which can surely control the density of the gypsum slurry fractionated from the mixer (fractionated slurry), which can restrict change of the flow rate of the fractionated slurry, and which can reduce the consumption of foam or foaming agent. The fractionation apparatus (30) fractionates the gypsum slurry from a mixer (4) for mixing calcined gypsum and water. The mixer has a hollow connector section (50), which allows the gypsum slurry to flow from a mixing area inside of the mixer into a chute section (5), and the chute section (5) discharging the inflow of gypsum slurry through its slurry discharge port onto a gypsum board liner paper. The fractionation apparatus has a slurry fractionation port (33) opening to the chute section or the hollow connector section, and causes a part of the gypsum slurry in the chute or hollow connector section to be delivered to a slurry delivery conduit (11,13,19).

Abstract: Disclosed are building board manufacturing techniques that minimize the build-up of slurry on associated forming equipment and also produce panels with enhanced physical properties. The methods involve applying a dissolvable film laminate to one or more fiber mats at the outset of the forming process. In the un-dissolved state, the film acts as a containment envelope for the gypsum slurry and any free floating glass fibers. During subsequent curing, the film is dissolved by vaporized water. In its dissolved state, the film is liquefied and coats the fibers of the underlying mat. This results in a building board with improved physical properties.

Abstract: A fibrous mat-faced cementitious article comprising (a) a cementitious core, and (b) a first fibrous mat comprising polymer or mineral fibers and a hydrophobic finish on at least one surface thereof, wherein the hydrophobic finish is in contact with the cementitious core, and a method of preparing a fibrous mat-faced cementitious article, as well as a method of preparing a water-resistant cementitious article comprising (a) preparing an aqueous siloxane dispersion, wherein the dispersion comprises about 4 wt. % to about 8 wt. % siloxane, (b) combining the siloxane dispersion with a cementitious mixture to provide a cementitious slurry, (c) depositing the cementitious slurry onto a substrate, and (d) allowing the cementitious slurry to harden, thereby providing a cementitious article.

Abstract: Disclosed is a method for inhibiting the growth of mold on building materials by application onto and/or incorporation into the building material of a mold-inhibiting composition comprising dehydroacetic acid or a salt thereof and, optionally, an additional fungicidal agent such as a quaternary ammonium compound. A preferred application of the method is the inhibition of mold growth on plasterboard (drywall).

Abstract: A gypsum board with multiple tapered edges has a flat, rectangular main flat body with four tapered edges. The main flat body is a gypsum core sandwiched between two paper sheets. The main flat body may be of any appropriate size, including 4 feet by 4 feet or other sizes. In a method for manufacturing the gypsum board with multiple tapered edges, a quantity of gypsum slurry is fed between two continuous paper sheets with a conveyor system to make a continuous gypsum sheet and longitudinal edges of the continuous gypsum sheet are tapered. The gypsum slurry is partially dried, and then the continuous gypsum sheet is transversely compressed between an upper bracket and a lower bracket to form a transverse tapered impression. The continuous gypsum sheet is cut at the tapered impression, and the transverse tapered edges are enclosed with finishing paper.

Abstract: The present invention is a method of making a backerboard having a fiberglass mesh on one side, and an impervious reinforcement membrane on the other side. The backerboard incorporates a low density, high compressive strength concrete core having an upper principal surface and a lower principal surface. The upper principal surface of the core is covered by a fiberglass mesh reinforcement layer, itself covered and bonded to the core by a thin layer of Portland cement. The lower principal surface of the backerboard is covered with a high tensile strength, impervious reinforcement membrane.

Abstract: Gypsum plaster board, containing a gypsum matrix and 0.1 to 10% by weight carbon particles, wherein the particle size (d50) of the carbon particles ranges from 0.5 to 4 mm.

Abstract: A production process is provided for a board of hydraulic binder with a facing on each of its sides. The process includes on one side first tapered parallel edges and on the same side or the other side, two second tapered parallel edges perpendicular to the first. The process also includes the use of a forming lath having at least two distal parts. The process can be used in a production line that includes a specific lath.

Abstract: A method includes outputting a semi-product of a core material for a gypsum board from a mixing tank. High-molecular adhesive is coated on inner faces of first and second outer layers that are bonded to two sides of the semi-product with the inner faces of the first and second outer layers engaged with the sides of the semi-product of the core material. After taking shape, the semi-product is severed and dried to obtain the core material for the gypsum board with the high-molecular adhesive forming high-molecular bonding layers between the core material and the first and second outer layers. The resultant gypsum board includes a core material and first and second outer layers securely bonded to two sides of the core material by high-molecular bonding layers formed by the high-molecular adhesive. Thus, the first and second outer layers are less likely to peel from the core material.

Abstract: The mention relates to a sheet coating article (1) intended to be applied to a wall (50), characterised in that it comprises: a tightly tined substrate (10), and a coating layer (20) disposed on the tightly tilting substrate (10).

Abstract: A ceiling tile of gypsum and cellulose fibers formed into a board by initially mixing the fibers and gypsum in a water-based slurry that is felted and thereafter pressed and dried with a desired board thickness, the dried board being processed to form a plurality of holes in a face thereof through at least the majority of the thickness of the board, the collective volume of the holes being sufficient to reduce the weight of the board by at least 10% and increase the NRC exhibited by the board over that which would otherwise be found in a board of the same composition without such holes.

Abstract: A process for making a fiber reinforced cementitious product such as a panel which hardens to an ultra-high compressive strength composite for use in making panels with ballistic and blast resistant properties. The panel has a continuous phase resulting from curing an aqueous mixture, in the absence of silica flour, of inorganic cement binder, inorganic mineral filler having a particle size of about 150-450 microns, pozzolanic mineral filler, and polycarboxylate based superplasticizer self-leveling agent, and water. The mixture may also include alkanolamine and acid or acid salt. The continuous phase may be reinforced with fiber distributed in the continuous phase before curing to form a panel. The panel may be reinforced with a fiber reinforced skin attached to at least one surface of the core, e.g., by lamination with an adhesive, e.g., epoxy, to form a ballistic and blast resistant cementitious armor panel.

Abstract: A gypsum board comprises a set gypsum layer having a first face and a second face. A fibrous mat is affixed to at least one of the faces. The mat comprises a non-woven web bonded together with a resinous binder. The web is composed of chopped continuous glass fibers having an average fiber diameter ranging from about 9.5 to 12.5 ?m. The board is exceedingly durable. It has a smooth surface that is readily finished in an aesthetically pleasing way, using paint or other wall covering systems.

Abstract: A method of making a gypsum panel comprises sandwiching a gypsum slurry between two moving sheets of facing material, one of said sheets comprising a fibrous facing material, curing and drying the gypsum slurry to form a set gypsum panel, applying a coating of a radiation curable formulation, which is essentially free of any unreactive components, onto the fibrous facing material of the set gypsum panel, applying a surface coating of an aggregate material onto the coating of the radiation curable formulation, and curing the coating of the radiation curable formulation with high energy radiation, wherein the radiation curable formulation comprises a high energy radiation curable polymer comprising ethylenically unsaturated double bonds.

Abstract: A manufacturing method of environmentally-friendly wallboard comprising the mixing a mortar of ash, slag, filler fibers, water and an alkali activator; and the distribution of said mortar on top of a mold corresponding to the width of the board, between single or double layers of a glass fiber web molded into each surface. Setting and curing are taking place at room temperature.

Abstract: A fibrous mat-faced cementitious article comprising (a) a cementitious core, and (b) a first fibrous mat comprising polymer or mineral fibers and a hydrophobic finish on at least one surface thereof, wherein the hydrophobic finish is in contact with the cementitious core, and a method of preparing a fibrous mat-faced cementitious article, as well as a method of preparing a water-resistant cementitious article comprising (a) preparing an aqueous siloxane dispersion, wherein the dispersion comprises about 4 wt. % to about 8 wt. % siloxane, (b) combining the siloxane dispersion with a cementitious mixture to provide a cementitious slurry, (c) depositing the cementitious slurry onto a substrate, and (d) allowing the cementitious slurry to harden, thereby providing a cementitious article.

Abstract: A vibrating flexible smoothing sheet or shroud disposed transversely of a direction of travel of a formed fiber panel including gypsum-cementitious slurry and embedded chopped fibers. The sheet is used to smooth the surface of the panel as it exits a fiber embedment station of a structural cementitious panel production line to remove grooves and other non-uniform surface imperfections to reduce the need for costly finishing after the panels are cured and cut to size. The flexible sheet is designed to float over the surface of the formed panel without tearing or otherwise damaging the surface of the heavily fiber reinforced surface layers of the panel. The vibrating sheet is pivotally mounted on the side dams of the web production line so it can float over the panel surface during use, but be raised off the line when not in use.

Abstract: A plaster slurry composition includes plaster, water and starch, the starch having a Brookfield viscosity of less than 60 cps at a temperature below 60° C. and a Brookfield viscosity greater than 10,000 cps at a temperature of 70° C.

Abstract: The present invention describes a fire resistant building material composition, useful for example as a fire door core and to a method of making this composition where the building material of the present invention is prepared from an aqueous slurry of calcined gypsum, paper fibers, a water insoluble organic binder, fiber reinforcement and a set retarder.

Abstract: The invention relates to a process for sticking edging material (10, 12) onto lightweight building boards (1) comprising two thin-walled outer layers (2, 4) and a core layer (6) of lightweight filler material disposed between the outer layers (2, 4), having the steps: provision of a lightweight building board (1), a decor edge (10) and a stabilizing edge (12), and sticking on of the decor edge (10) and/or the stabilizing edge (12) in the region of a narrow surface (1?) of the lightweight building board (1). The process according to the invention is characterized in that at least the stabilizing edge (12) comprises a synthetic fiber material, preferably a cellulose-based fiber material, particularly paperboard material.

Abstract: A system and method of making a plaster panel to use in the construction of a wall of a building in a relatively faster, easier, more efficient, and more precise manner for either interior or exterior walls is disclosed. The created plaster panels may include a slab of cementitious composition including a mixture of sizes of cut expanded polystyrene, a quantity of monofilament fiber, and a binding agent. At least one layer of a mesh may surround the slab, wherein the resulting panel is light in weight, flexible and strong. Such panels may be fixed in place to a building frame by suitable fasteners such as nails or screws, while causing little or no fracturing of the panel.

Abstract: Disclosed herein are embodiments of foam backing panels for use with lap siding and configured for mounting on a building. Also disclosed are lap siding assemblies and products of lap sidings. One such embodiment of the foam backing panel comprises a rear face configured to contact the building, a front face configured for attachment to the lap siding, alignment means for aligning the lap siding relative to the building, means for providing a shadow line, opposing vertical side edges, a top face extending between a top edge of the front face and rear face and a bottom face extending between a bottom edge of the front face and rear face.

Abstract: A process and apparatus for forming wallboard panels having recessed edges along all four edges which process involves passing an unfinished length of wall board through a lateral recess forming apparatus.

Abstract: The invention generally provides gypsum-containing slurries including stucco, naphthalenesulfonate dispersant, and pregelatinized starch. The naphthalenesulfonate dispersant is present in an amount of about 0.1%-3.0% by weight based on the weight of dry stucco. The pregelatinized starch is present in an amount of at least about 0.5% by weight up to about 10% by weight of pregelatinized starch by weight based on the weight of dry stucco in the formulation. Other slurry additives can include trimetaphosphate salts, accelerators, binders, paper fiber, glass fiber, and other known ingredients. The invention also comprises the gypsum-containing products made with such slurries, for example, gypsum wallboard, and a method of making gypsum wallboard.

Abstract: A vibrating flexible smoothing sheet or shroud disposed transversely of a direction of travel of a formed fiber panel including gypsum-cementitious slurry and embedded chopped fibers. The sheet is used to smooth the surface of the panel as it exits a fiber embedment station of a structural cementitious panel production line to remove grooves and other non-uniform surface imperfections to reduce the need for costly finishing after the panels are cured and cut to size. The flexible sheet is designed to float over the surface of the formed panel without tearing or otherwise damaging the surface of the heavily fiber reinforced surface layers of the panel. The vibrating sheet is pivotally mounted on the side dams of the web production line so it can float over the panel surface during use, but be raised off the line when not in use.

Abstract: A composition for the manufacture of a gypsum board comprising hydrated pregelatinized starch, sulfonated styrene butadiene latex and stucco with 0.4 to 3 wt. % of starch based on the stucco weight is disclosed. The composition provides enhanced strength in the absence of other strengthening agents.

Abstract: The subject of the invention is a novel plasterboard and its manufacturing processes. The novel board comprises, on one side, two first parallel feathered edges and, on the other side, two other, second, parallel feathered edges that are perpendicular to the first ones; or, on one side, two first parallel feathered edges and, either on the same side or on the other side, two second parallel feathered edges that are perpendicular to the first ones, the said other parallel feathered edges having a width of between 100 and 200 mm; or, on one side, two first parallel feathered edges and, either on the same side or on the other side, two second parallel feathered edges that are perpendicular to the first ones, the said second parallel feathered edges having a width such that the ratio of the width of the said second parallel feathered edges to the width of the said first parallel feathered edges is between 1.5 and 5.

Abstract: A method of forming a wallboard material can include forming a mixture including microparticles, sodium silicate and vinyl acetate. The mixture can be disposed between a metallic facing membrane and a second facing membrane. The mixture can then be heat cured in a single step sufficient to form a wallboard material having the metallic facing membrane and the second facing membrane attached to a core matrix. The heat curing time is complete in less than about 1.5 hours without causing damage to the wallboard material.

Abstract: A fibrous mat faced gypsum panel having on at least one of the facing sheets a moisture resistant, cured coating of a radiation curable, e.g., UV curable, polymer.

Abstract: A gypsum board comprises a set gypsum layer having a first face and a second face. A fibrous mat is affixed to at least one of the faces. The mat comprises a non-woven web bonded together with a resinous binder. The web is composed of chopped continuous glass fibers having an average fiber diameter ranging from about 9.5 to 12.5 ?m. The board is exceedingly durable. It has a smooth surface that is readily finished in an aesthetically pleasing way, using paint or other wall covering systems.

Abstract: A manufactured construction board is formed from a composition that may include magnesium oxide, magnesium chloride, a binding agent (e.g., perlite), wood shavings, recycled board scraps, and water. The construction board further includes fiberglass and polyester paper sheets on opposite sides of the construction board. A method of fabricating the construction board is also disclosed to include mixing magnesium chloride with water to form a solution, mixing the solution with magnesium oxide, perlite and a binding agent to form a paste, and pouring the paste onto a mold to form a construction board. The paste is poured onto a mold which is then passed through a series of rollers to spread out the paste evenly across the mold and to form the paste into the desired thickness. The resulting construction board is fire and water resistant and much more durable than conventional sheetrock.

Abstract: A method for producing plaster plates (44), according to which two fine cardboard-covered sheets of paper (8, 9) enclose a plaster-based hydraulic binder (10) in a shaping device (13), creating a composite band (45) that is hardened on one or several hardening bands (14, 15), the edges of said hardening bands (14, 15) being provided with two bands used for tapering in the horizontal direction.

Abstract: A gypsum composition comprising water, stucco, clay, an amine compound, a polyoxyalkylene, and a comb-branched copolymer is disclosed. The gypsum composition has improved fluidity. A method for preparing the gypsum composition is also disclosed. The method comprises mixing the components to form a slurry, casting the slurry into a product, and drying the product.

Abstract: This invention is directed to a method of reducing the water demand of expanded perlite that includes obtaining a vibrating screen supported at an angle and placing expanded perlite on the vibrating screen. The expanded perlite is moved over the screen past toward a burner at a rate that heats the expanded perlite to a temperature sufficient to anneal it. The expanded perlite is then moved away from the burner and allowed to cool. Another embodiment of this invention is directed to a method of making a gypsum product. The method includes annealing perlite by the method described above, then preparing a slurry of calcium sulfate hemihydrate, additives, water and the annealed perlite. The slurry is formed into the shape of the gypsum product and allowed to set. This process is particularly useful in making gypsum panels and acoustical panels that benefit from the use of lightweight materials.

Abstract: A method enables gypsum/fiber board to be manufactured such that recessed areas are formed on the same face of the cut wallboard on all four edges without interrupting the production line. The system accommodates different lengths of cut wallboard as the lateral cut edge recess forming apparatus is adjustable in width to accommodate different lengths of cut wallboard.

Abstract: Disclosed herein is a trough-edge building panel used in the fabrication of panelized wall systems with elastomeric joints that are resistant to cracking. The panels are preferably fiber cement. The front surface of each panel has a trough adjacent to an edge of the panel. Panels are fastened to a frame with the trough-edges adjacent to each other. A joint tape is applied to the seam between the panels such that the edges of the joint tape fall within the troughs of the adjacent panels. The wall is then finished with an elastomeric finish. Also disclosed is a method of manufacturing the trough-edge panels.

Abstract: A mold-resistant gypsum panel includes a core of an interlocking matrix of calcium sulfate dihydrate crystals, a facing material on at least one side of the panel and a salt of pyrithione dispersed through both the core and the facing materials. A method of making a mold-resistant gypsum product is also provided. A slurry of calcined gypsum, water and a water-soluble pyrithione salt is formed, then deposited on a sheet of facing material. The slurry on the facing material is shaped into a panel and maintained under conditions sufficient for the calcined gypsum to react with the water to form a core comprising an interlocking matrix of set gypsum crystals. Heating of the panel causes evaporation of the water that did not react with the calcined gypsum.

Abstract: Gypsum board having inorganic fiber, preferably glass fiber, preferably glass fiber, includes providing face sheets which have been completely impregnated with a gypsum slurry so as to penetrate through said random interstices between the inorganic fibers and to thereby cover the board surfaces with gypsum slurry. The gypsum board product is formed by passing the wet gypsum board through a board forming station having double forming plates, an upper forming plate having at least a portion thereof being set at a predetermined angle relative to a lower forming plate and having a separation between the forming plates defining a predetermined dimension substantially equal to the desired thickness of the manufactured gypsum board product. The method provides a multilayer gypsum board having a polymeric compound added to unset gypsum so as to provide a gypsum board ready for finishing.

Abstract: A method is provided for continuous production of gypsum boards which comprises forming a laminate of gypsum slurry between a facing paper and a backing paper and continuously forming a longitudinal recess along the side edges of the laminate surface, and a lateral recess at spaced intervals on the laminate surface thereby producing a four-tapered edge gypsum board which is uniquely suitable as a material of construction in the building industry.

Abstract: A method enables gypsum/fiber board to be manufactured such that recessed areas are formed on the same face of the cut wallboard on all four edges without interrupting the production line. The system accommodates different lengths of cut wallboard as the lateral cut edge recess forming apparatus is adjustable in width to accommodate different lengths of cut wallboard.

Abstract: A method of making a gypsum board includes mixing together gypsum and water in a mixer to form a gypsum slurry; discharging the gypsum slurry onto a first facing sheet; laying a second facing sheet on top of the discharged gypsum slurry; passing the gypsum slurry and facing sheets through a forming station to form the slurry to a desired thickness; allowing the formed gypsum slurry to set; removing at least one of the facing sheets from the set gypsum; cutting the set gypsum into boards; and drying the cut gypsum boards.

Abstract: A method for making wallboard or backerboard sheets which are relatively lightweight, strong, and which have good fire resistance, thermal insulation, and sound absorbing properties includes forming core material having opposing first and second major surfaces and comprising aerated concrete, securing at least one face layer on at least one of the first and second major surfaces of the core material, and cutting the core material and at least one face layer secured thereto into a plurality of wallboard or backerboard sheets. The provision of aerated concrete for the core provides many key advantages over conventional gypsum wallboard sheets, and/or conventional backerboard sheets, such as gypsum greenboard or cementitious backerboard, for example. In one class of embodiments, the method may further include curing the core material prior to securing the at least one face layer thereto. In another class, the method may further include curing the core material after securing the at least one face layer thereto.

Abstract: A method for manufacturing sheets of plasterboard includes (i) forming the sheet; (ii) setting it by hydration until a hydrated product with a content of below 80% is obtained; (iii) continuing hydration in at least one revolving barrel; and (iv) drying. The revolving barrel includes a number of branches.