Abstract: A method for manufacturing sheets of plasterboard includes forming the sheet; setting the sheet with hydration; and drying while the sheet is being rotated. A barrel is used for drying.

Abstract: A reinforced plasterboard has a first layer of paper, a core of a cementitious material, a mesh reinforcement and adjacent to that mesh reinforcement a further layer of paper. The mesh may be in contact with the paper layer.

Abstract: A method of manufacture of multilayer gypsum board, and a multilayer gypsum board, having face sheets comprising randomly oriented inorganic or glass fibers completely impregnated with a gypsum slurry penetrating through the random interstices between the inorganic fibers and coating the board surfaces with gypsum slurry. Wet gypsum board passes through a board forming station having upper and lower forming plates, set at an angle relative to each other and being separated by a predetermined dimension substantially equal to the desired thickness of the manufactured gypsum board product. Additives in the gypsum, such as engineered polymers, provide for a better surface for coating. The gypsum board has a first layer of a mixture of set gypsum having an outer surface and the polymeric compound additive entrained therein and impregnated in a thin sheet of randomly aligned inorganic fibers to essentially encase the core gypsum within two facing layers.

Abstract: A method of manufacture of gypsum board having inorganic fiber, preferably glass fiber, 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 coat the board surfaces gypsum slurry. A 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.

Abstract: A method of manufacturing a composite product comprising providing a substrate layer and a slurry formulation including a hydraulic binder and dewatering agent. The slurry is then applied to the substrate layer to form a functional layer and the functional layer dewatered through the substrate layer. The application of the slurry to form the functional layer and dewatering steps can be repeated to build up a laminated composite product. Functional additives may be included in each layer to provide desired properties to that layer and indeed to the subsequent composite product.

Abstract: A method for forming a laminated sheet material from a slurry having a liquid component.

Abstract: The present invention comprises apparatus for the manufacture improved structural panel with synthetic ingredients, such as vermiculite and fibers. The improved structural panel achieves enhanced lateral and surface integrity by the use of fibers within the core of the structural panel and adhesives and smooth materials (such as foil) as a surface coating. The apparatus is particularly suited for manufacture of the structural panel at low cost and high efficiency.

Abstract: A gypsum/fiber board having improved impact resistance is produced by mixing predetermined amounts of fibers, calcined gypsum and water to form a mixture of wetted, loose fibers; laying out a reinforcing mesh over the upper surface of a forming belt; depositing said mixture on said mesh to form a layer of said mixture, said; and compressing said mesh together with said layer of mixture to embed said mesh in the lower surface of said layer to form a board composed of bonded fibers and gypsum with said mesh embedded in the surface thereof.

Abstract: A system for making wallboard or backerboard sheets may include a mixer for mixing materials for making aerated concrete, at least one face layer supply, and a former downstream from the mixer for forming core material having opposing first and second major surfaces and comprising aerated concrete. The former is preferably also for securing at least one face layer from the at least one face layer supply onto at least one of the first and second major surfaces of the core material. The former may include a mold downstream from the mixer for receiving the materials for making aerated concrete therein and allowing the materials to rise and stiffen into a body, an autoclave downstream from the mold for curing the body, and a saw blade downstream from the autoclave for sawing the body into sheets of core material. A magnetic field generator is provided adjacent the saw blade for causing the saw blade to be substantially flat to saw substantially flat sheets of core material from the body.

Abstract: A novel wallboard composition is disclosed comprising a unique combination of synthetic binders selected for their ability to establish a strengthened permanent bond in the final dry state for use in a wallboard composition comprising primarily gypsum, and in a wallboard composition comprising an expanded mineral such as Perlite which largely reduces the amount of gypsum over current gypsum wallboard formulations, thus reducing the weight while maintaining the strength of the wallboard structure. In a preferred embodiment, the lightweight, strengthened wallboard of the present invention also comprises an optional covering veneer that is applied to the top ply of the face paper to provide increased strength, moisture resistance, and fire retardency, and the back paper top ply is treated to provide increased flexural strength.

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 novel wallboard composition is disclosed comprising a unique combination of synthetic binders selected for their ability to establish a strengthened permanent bond in the final dry state for use in a wallboard composition comprising primarily gypsum, and in a wallboard composition comprising an expanded mineral such as Perlite which largely reduces the amount of gypsum over current gypsum wallboard formulations, thus reducing the weight while maintaining the strength of the wallboard structure. In a preferred embodiment, the lightweight, strengthened wallboard of the present invention also comprises an optional covering veneer that is applied to the top ply of the face paper to provide increased strength, moisture resistance, and fire retardency, and the back paper top ply is treated to provide increased flexural strength.

Abstract: A system for making wallboard or backerboard sheets may include a former for forming core material having opposing first and second major surfaces and comprising aerated concrete, and for securing at least one face layer from at least one face layer supply onto at least one of the first and second major surfaces of the core material. The former may include a saw blade for sawing bodies of cured aerated concrete into sheets of core material, a lower conveyor for advancing a series of bodies past the saw blade, and an upper conveyor for conveying a remaining portion of a body downstream from the saw blade back to a position upstream from the saw blade. Accordingly, the former provides for the efficient processing of relatively large cured bodies of aerated concrete to be formed into wallboard or backerboard sheets.

Abstract: A system includes a saw comprising at least one saw blade for sawing at least one body of aerated concrete into sheets of core material having opposing major surfaces, at least one face layer supply, and a conveyor for advancing the sheets of core material along a path of travel as at least one face layer is secured thereto from the at least one face layer supply. The system may further include a shuttle for repetitively advancing the at least one body of aerated concrete past the at least one saw blade to saw successive sheets of core material. The shuttle, in turn, may comprise a car for carrying the at least one body of aerated concrete, a track for guiding the car, and at least one actuator for moving the car along the track. The saw blade may extends in a substantially horizontal direction. Accordingly, the saw may further comprise a vertical indexer for vertically indexing the at least one saw blade to saw successive sheets of core material.

Abstract: A novel construction board composition is disclosed comprising a unique combination of synthetic binders selected for their ability to establish a strengthened permanent bond in the final dry state for use in a construction board composition comprising primarily gypsum, and in a construction board composition comprising an expanded mineral such as Perlite which largely reduces the amount of gypsum over current gypsum construction board formulations, thus reducing the weight while maintaining the strength of the construction board structure. In a preferred embodiment, the lightweight, strengthened gypsum construction board of the present invention also comprises an optional covering veneer that is applied to provide increased strength, moisture resistance, and fire retardency, and the back paper top ply is treated to provide increased flexural strength.

Abstract: An improved method for texturing gypsum fiber panels and producing surface textured panels, edge tapers, and deeper patterned wainscot-type panels, involving the use of a flexible die with a textured surface. The die is pressed onto the panel in its slurry state just after the onset of an exothermic rehydration reaction. Partial hydration and setting occur during pressing by the die to form a textured mat. The mat is removed from contact with the die at a point along the rehydration temperature curve about at or less than one-half of the rise to the greatest rehydration temperature.

Abstract: A process for reducing rollups in gypsum board panels when the panels are laminated with a laminate, is provided. A laminator is provided, as is at least one gypsum board panel, each panel having a face paper layer and a backing paper layer. Each paper layer has a coefficient of friction, and at least one of the face paper layer and the backing paper layer is treated with an agent for reducing the coefficient of friction and water absorbency. Next, a supply of laminate is provided and installed in the laminator. Then, at least one panel of the gypsum board is fed through the laminator, so that a layer of the laminate is applied thereon.

Abstract: The present invention provides an architectural material obtained by forming a decorative layer containing calcium carbonate as a binder component on the surface of a base material, and laminating a ventilating protective sheet having a peeling strength of 200 to 4000 mN on the surface of the decorative layer without interposing an adhesive layer separately, and a process for producing the architectural material. The architectural material has excellent soiling resistance or abrasion resistance, and is highly practical.

Abstract: Activated clay is mixed with fine sawdust and/or powder of the heart of kaoliang stalk, a small amount of a coloring agent and bittern containing calcium sulfate, calcium silicate, magnesium or magnesium chloride and the like, or a composition of components identical to the bittern in a paste phase. Then, the paste phase mixture is supplied together with glass fiber layers provided on the upper and the lower sides of the mixture separately on any one of molding plates selected from glass, acryl, polycarbonate, polyvinyl chloride or polypropylene. The materials of the molding plates, in situ, are passed through mixture-separative sandwich rollers to give a certain thickness of a mixture sheet by pressing. The surface of the mixture sheet is coated with an epoxy resin layer to provide a flat and slick surface. On the epoxy resin layer an adhesive layer, transfer film layer, ultraviolet curable adhesives and a protection film layer are coated by adherence in turn to provide an incombustible board.

Abstract: An inorganic board consisting of an inorganic base layer formed by a paper making method and an inorganic surface layer formed by the dry method on said inorganic base layer is provided in the present invention. A synthetic resin emulsion and/or a rubber latex is coated on and permeates said inorganic base layer so as to supply the water to said inorganic surface layer and improve the delamination strength between said inorganic base layer and said inorganic surface layer.

Abstract: Method of manufacturing an electrical connection, and connection thus obtained between a strip of a plastic material (1) having a conductive coating on a single face (5) and a second conductor (15) positioned on the non-conductive side (3) of said strip consisting of forming into a loop the lug (7), formed by the end portion of said strip, by thermoforming between two parallel cylinders of which at least one is heated, driven in rotation to come to press the non-conductive face of the lug (7) against a non-conductive portion of the strip.

Abstract: A wood veneer laminated gypsum board comprises a gypsum core and lamination f a paper or a paper-like outer layer on both sides, an aluminum backed wood veneer bonded to the paper outer layer, and debossed designs on the wood veneer which penetrates beyond the surface of the gypsum board. The wood veneer laminated gypsum board is formed by spraying or applying a mixture of adhesive diluted with liquid softening agent, which may include water or water mixed with other materials, on the aluminum side of the aluminum-backed wood veneer. The paper or paper-like outer covering is lightly sprayed or coated with the softening agent. The coated aluminum backed wood veneer is placed on the lightly coated the gypsum board. The wood veneer is moistened with water. The wood veneer and the gypsum board is pressed with application of heat for a predetermined period.

Abstract: Production of plasterboard includes spreading of a mixture formed of gyps fibers and water onto a continuously moving belt to form a spread layer subsequently precompressed to 110% to 180% of a final board thickness and successively wetted from both sides and thereafter compressing the wetted layer to the final board thickness.

Abstract: This invention relates to a panel of material comprising a film comprising a layer of a solid polyolefin and a layer of copolyester wherein said copolyester comprises:(1) a dicarboxylic acid component comprising repeat units from at least 90 mole percent terephthalic acid; and(2) a diol component comprising repeat units from 20 to 40 mole percent diethylene glycol and 80 to 60 mole percent ethylene glycol, based on 100 mole percent dicarboxylic acid and 100 mole percent diol,said layer of a copolyester being intimately bonded to a wooden substrate and said polyolefin layer being exposed on the outer surface of said film.

Abstract: Composite panels with high fire-proofing capacity have two outer layers and a core that features a core mixture containing aluminum hydroxide in compacted form, lightweight fillers, in some cases fine grained or splintery aluminum hydroxide, as desired magnesium hydroxide and polymer-based binding agents. The composite panels are suitable e.g. as facade panels for building constructions.

Abstract: A method of, and compositions for, the making of a fire-resistant door core assembly. Doors produced from the door core assemblies. In the making of a door core assembly, an aqueous slurry containing gypsum cement and diatomaceous earth is prepared. The slurry may also include expanded mineral ore material and Portland cement. The slurry preliminarily hardens during a green cure stage.

Abstract: Plasterboard is made by first spreading a mixture of plaster, fibers and er and then pressing this moist mixture to form the raw board. The upper and lower surfaces of the raw board are then wetted and the thus wetted raw board is pressed with a pressure less than the original consolidation pressure.

Abstract: A flame resistant to nonflammable composite panel is produced from a nonextrudable core mixture with a pourable, nonflammable filling material and a binder, and on both sides cover strips flexibly bonded to the core. For a continuous production of the composite panel in one operation, the core mixture is poured onto an inrunning lower cover strip, in contact with a lower adhesive film facing the core mixture, and a pile is formed there, extending over the entire width of the adhesive film, both continuously and uniformly drawn through a V gap and compacted there for the first time and calibrated to thickness, an upper adhesive film, upwardly limiting the precompacted core mixture, is fed in and brought into contact with a continuously fed cover strip and the sandwich is pressed with further compaction, heated, cooled and cut to the final length of the composite panel.

Abstract: A lightweight wallboard having a density in the range of 10 pcf to 30 pcf and comprised of a faced layer of expanded siliceous inorganic particles, such as expanded perlite, bonded together by inorganic binder, such as sodium silicate. The board is made by depositing a mixture of particles, binder and water onto a moving web of facing material, contacting the mixture with an upper moving web of facing material, compacting the mixture to the desired shape and density and drying the resulting board. Fire resistant and water repellent versions of the formula are also disclosed.

Abstract: A method for making gypsum wall board in which during the production of the board pressure is applied to a portion or all of the board surface to reshape, compress and densify the gypsum core to change the shape or contour the face surface of the gypsum board. The pressure must be applied in a systematic fashion to avoid creating lateral shifting or shear stresses in the gypsum core or between the core and paper surface to avoid destroying the paper to gypsum core band. The method can be used to product a cross taper at the cut ends of the board, to produce a decoratively shaped board surface and to densify the entire board core for special gypsum board applications.

Abstract: A method for incorporating siloxane into a water-resistant, gypsum-based article is disclosed, comprising, (A) adding said siloxane to water; (B) mixing said siloxane/water mixture with calcined gypsum to form an aqueous slurry; and (C) allowing said slurry to set to form a set gypsum-based, water-resistant article.

Abstract: In the improved gypsum board in accordance with this invention, the board has a gypsum core and first and second cover sheets of fibrous material on opposing faces. The core has a first stratum parallel to and adjacent the first cover sheet. This stratum does not contain any fibers of the fibrous material. This first stratum has relatively few voids and a substantially greater density than the central portion of the core of the board. The central portion of the core has a plurality of relatively large discrete voids substantially uniformly distributed throughout the central portion of the core. These voids have substantially spherical coherent walls.

Abstract: A mixture of waste, essentially cellulosic material and a fire proofing solution can be used to make building materials with exceptional qualities. These qualities include fire proofing, vermin proofing, water proofing and excellent insulative values, for example. Additionally, this process represents an excellent method for recycle of these waste materials. A sheetrock-like or wall-board material can be made therefrom, one which can be nailed, screwed, drilled and fastened without causing serious damage to the surface or the element itself.

Abstract: In the process for making gypsum fiberboard the boards are formed or molded rom a mash containing calcium sulfate dihydrate and fiberous material. By heating and subsequently cooling the boards the dihydrate is first converted into the hemihydrate and subsequently recrystallized again to the dihydrate. Known processes require day line setting times which are economically disadvantageous. According to the present invention these times are shortened by pulling or drawing water, an aqueous solution or a water containing mixture through the boards after the cooling step. Advantageously a setting accelerating agent can be dissolved in the water. By these features the setting time can be shortened to less than two hours. By addition of a binding agent, e.g. starch, to the fluid drawn through the boards the strength of the boards is increased.

Abstract: A method for the production of fibrous plaster boards for which a suspension is prepared from wet-digested fiber material and calcium sulfate dihydrate, the suspension is formed into a board with removal of water, and the dihydrate is recrystallized with heating at atmospheric pressure to a hemihydrate which is subsequently converted back into the dihydrate by the addition of water. For this purpose, the suspension is dewatered from a water content of about 300 to 600% to one of about 30 to 40% in dewatering equipment, the dihydrate is recrystallized in air and without pressure to the beta form of the hemihydrate and the water, required for setting, is aspirated through the board by suction.

Abstract: A tapered edge wallboard, for monolithic wall construction, in which the taper is formed by removal of core material along an edge, as by a saw cut, and a thin layer of edge material is bent inward, closing the saw-cut groove and resulting in a taper.

Abstract: In the manufacture of cementitious board by depositing a slurry of hydraulic cementitious material, commonly gypsum plaster, between two facing sheets and forming it to the desired width and thickness prior to setting, the formation of voids in the core, due to air trapped in the slurry is avoided by vibrating the lower sheet (10) after the slurry (15) has been deposited on it, usually before the upper sheet (14) contacts the slurry, and subsequently vibrating the upper sheet when it comes into contact with the mass of cementitious slurry. The vibration of the lower sheet, for example by rotating polygonal shaft (20), causes bubbles of unwanted trapped air to rise through the slurry towards the upper surface and the accumulated bubbles are then broken by the vibration of the upper sheet, which may be accomplished by a second rotating shaft (21), before they become incorporated into the formed board as voids.

Abstract: A method of surface treatment for plaster articles to improve wear and water resistance is disclosed. The method includes the step of forming the article, allowing the article to set, drying to remove excess water, applying a coat of substantially molten Candelilla wax onto an exterior surface of said article, maintaining said wax at a temperature of no less than 155.degree. F. (68.degree. C.) for sufficient period of time to allow said wax to substantially fill exterior pores and irregularities, and cooling said article to solidify the wax. Also disclosed is a wear resistant and water repellent plaster article comprising a formed plaster article having an exterior surface portion thereof coated with a thin layer of Candelilla wax, said coated surface portion providing a substantially water impregnable barrier and providing enhanced wear resistance.

Abstract: A wooden board for use for example as a table top has a moisture-proof coating on its upper surface and an edging of synthetic material which is sprayed under pressure on to the cut edge surface of the board. The edging overlaps the adjacent edge of the upper surface of the board and penetrates a profiled cut-out in the edge surface. In order to give a good moisture seal, the cut-out profile has an inwards directed back cut immediately under the upper board surface and a lower outwardly directed projection.

Abstract: The invention provides a process and apparatus for producing fabric-reinforced, thin concrete panels suitable as a backer board for construction materials such as ceramic tile, slate and thin brick. A process is described whereby the components of the panel are deposited on a web of disposable carrier/release material such as polyethylene coated paper while moving on a conveyer belt to form a continuous strip, the strip is cut into panels and the wet, uncured panels are stacked by means of an air-float stacking unit, then subsequently cured.

Abstract: Fiber containing plaster boards are prepared by superimposing a plurality of board blanks one on top of the other such that the direction of the fiber orientation in the superimposed blanks deviates one from the other. The board blanks are formed in a conventional manner from a suspension of calcium sulfate capable of setting, reinforcing fibers and a quantity of water beyond the quantity of water necessary for setting the calcium sulfate capable of setting. After mechanically removing excess water from the suspension to form the board blanks, two or more of these blanks are placed one on top of the other and are connected under pressure and dried. Thereafter, a predetermined number of board blanks having a direction of the fiber orientation deviating one from the other, are placed one on top of the other and are pressed together prior to or during the setting of the calcium sulfate.

Abstract: A method for forming shaped articles from glass fiber reinforced gypsum. An aqueous slurry of calcium sulfate hemihydrate, water and glass fibers contains between 22 and 45 parts by weight water, 100 parts by weight calcium sulfate hemihydrate and 3 to 10 parts by weight glass fiber. The slurry is provided as a continuous ribbon on a moving, water-impermeable first membrane. A water-impermeable second membrane is applied above the continuous ribbon and sealed along its side edges to the side edges of the first membrane to form a sandwich consisting of the two membranes and the slurry ribbon.The sandwich is shaped prior to the setting of the gypsum and is retained in the desired shape until initial setting occurs. Thereafter at least a portion of one of the two membranes is removed and substantially all of the uncombined water is removed from the shaped ribbon.

Abstract: Disclosed is a gypsum board having a kerfed edge along substantially the full length of at least one edge wherein the kerf has sidewalls inclined opposingly inwardly toward one another but do not intersect and are joined by a bottom surface of uneven profile characterized by alternately and irregularly spaced projections and depressions. The uneven bottom surface and each sidewall meet at a jagged intersection. Said kerfed edge provides enhanced strength in a direction perpendicular to the sidewalls providing improved board retention by flanged supports over that of conventional mechanically sawn kerfed edge boards. A process for providing kerfed edge gypsum board is also disclosed which comprises projecting into the board edge a first and second fine stream of aqueous liquid which incline toward one another at angles of incidence to a line perpendicular to the board edge which provides a combined angle therebetween of from about 3.degree. to about 20.degree..

Abstract: Plaster board panels wherein at least the top layer of one of the two cardboard sheets contains polyolefin fibrides can be easily dehydrated during their manufacture because of the porosity of the cardboard sheets. The finished panels have a substantially sealed surface of low porosity which is resistant to wet treatment and thus suitable for the application of various painting and coating systems.

Abstract: A predecorated printed paper on the gypsum wallboard with a clear washable coating over the printed paper, and having a thin coating of polyethylene emulsion on the back paper which overcomes the tendency of the coated predecorated paper to stick to the back paper of an adjacent board when the boards are piled in stacks for storage and shipment.

Abstract: An improved terrazzo floor or wall construction of reduced thickness bonded and adhesively secured to an underlying sub-surface through the medium of an intermediate liquid impermeable sheet. A frangible terrazzo veneer is bonded to the liquid impermeable sheet and the sheet in turn is adhesively secured to the underlying sub-surface by a rubberized asphalt or the like elastomeric material to permit lateral movement of the sub-surface relative to the said facing veneer to obviate cracking of the veneer due to cracking or lateral movement of the sub-surface.

Abstract: A composite panel-board is made up of a rigid, gypsum board, base panel having a rigid, organic plastic, foam layer formed in-situ on, self-adherent to, and essentially covering one of the broad, flat surfaces of the gypsum board base panel. A water-vapor-resistant, flame-retardant layer is adherent to and covers the otherwise exposed, broad surface of the rigid foam layer. The composite panel-board is fabricated by attaching upwardly extending edge sheets on or adjacent to the mutually opposite, side edges of the gypsum board panel so that the mutually opposite edge sheets, together with the gypsum board panel, form a trough. The upper surface of the gypsum board panel is heated to a temperature of at least about 95.degree. F in the presence of a water unsaturated atmosphere, and then a uniform layer of a foamable, liquid, organic plastic material is applied to the upper surface of the gypsum board panel.

Abstract: A predecorated wall panel is disclosed for use in forming walls in which the joints between the panels are not to be finished. The panel includes a rigid core of green hydrated gypsum with a layer of resilient deformable material along at least one edge thereof being adhesively affixed thereto and a decorative sheet covering the front surface and side edge surface of the panel with a decorative sheet being under tension in the vicinity of one edge surface thereby partially compressing the deformable material and enabling two or more panels to be positioned with a core edge surface adjacent to each other thereby presenting an attractive appearance.

Abstract: In the production of decorative gypsum board, wherein a hemihydrate gypsum slurry is continuously injected between decorative gypsum board card paper and conventional gypsum board card paper and the thus slurry-injected sheets are pressed by a suitable means to form the sheets in a predetermined thickness and then dried to form the decorative gypsum board, the improvement comprising coating with an urethane resin solution over decorative low-weight basis paper such as tissue paper or machine glazed white paper, drying the coated paper and laminating the resultant paper to a gypsum board card paper to obtain said decorative gypsum board card paper.