A method and device for producing lightweight panels with a core of gypsum or of cement and gypsum, with pores for decreasing volumetric weight, and with a covering made of cardboard or of a sheet of glass fibers. The production line does not change except for the addition of a device which forms closed hollow cavities within a suspension in an area where an upper sheet covers the suspension. Air pressure which is fed into the formed cavities is slightly higher than the hydraulic pressure of the suspension, so as to prevent the gaps being filled by the suspension. The layers are less thick, and the type and dimensions of the cavities and the thickness of the walls are varied depending on the desired qualities of the panels.

A neutron beam shielding gypsum-based building board includes gypsum, a boron-containing material containing boron an amount of which is in a range from 1.0 parts by mass to 120 parts by mass with respect to 100 parts by mass of the gypsum, and a water reducing agent in a range from 0.05 parts by mass to 2.0 parts by mass with respect to 100 parts by mass of the gypsum. The boron-containing material includes one or more kinds selected from calcium borate, boron carbide, boric acid, boron oxide, sodium borate, and calcium boride, and a specific gravity in a dry condition is in a range from 0.65 to 1.6.

Gypsum panels and methods of making the same are provided. A method of making a gypsum panel includes forming a first gypsum slurry by combining stucco, water, a siliconate, and a phosphate salt or polymer, and setting the first gypsum slurry to form at least part of a core of the gypsum panel, wherein the gypsum panel displays a 2-hour water absorption test weight increase of at least 10 weight percent less than an otherwise identical comparative panel containing no phosphate salt or polymer in its core.

Gypsum panels and methods of making gypsum panels are provided. Methods of making gypsum panels include: depositing a first gypsum slurry onto a first surface of a first fiberglass mat; allowing the first gypsum slurry to set to form at least a portion of a gypsum core; and applying a substantially continuous barrier coating comprising a polymer binder to a second surface, opposite the first surface, of the first fiberglass mat, in an amount of from about 1 lb/MSF to about 40 lb/MSF, such that the substantially continuous barrier coating has an average thickness of from about 1 micron to about 100 microns, wherein the substantially continuous barrier coating eliminates at least 99 percent of pin holes present in the exposed second surface of the first fiberglass mat.

A method of preparing a gypsum-based product comprises the steps of mixing calcined gypsum with polymer particles and water to provide a slurry. The polymer particles comprise principally polyvinyl acetate, and have a particle size distribution, measured using laser diffractometry, such that particles having a diameter of 4.5 μm or less provide at least 90% of the total particle volume.

An impact resistant exterior sheathing gypsum building panel with an integrated impact resistant woven mesh which protects against impact from projectiles such as those conveyed by hurricane force winds is provided. Methods for manufacturing these exterior sheathing gypsum building panels with an integrated impact resistant woven mesh are also provided. An exterior sheathing system employing the exterior sheathing cementitious building panel is provided.

An ultrastable cementitious material with nano-molecular veneer makes a cementitious material by blending 29 wt % to 40 wt % of a magnesium oxide dry powder containing 80 wt % to 98 wt % of magnesium oxide based on a final total weight of the cementitious material, with 14 wt % to 18 wt % of a magnesium chloride dissolved in water and reacting to form a liquid suspension, mixing from 2 to 10 minutes, adding a phosphorus-containing material, and allowing the liquid suspension to react into an amorphous phase cementitious material, wherein a portion of the amorphous phase cementitious material grows a plurality of crystals. The plurality of crystals are encapsulated by the amorphous phase cementitious material forming a nano-molecular veneer. A process to make the ultrastable cementitious material. A tile backer board incorporating the ultrastable cementitious material and a process for making the tile backer board.

The present disclosure relates to plaster boards and methods for making them. For example, one aspect of the disclosure is a plaster board comprising one or more continuous layers of material disposed within a body of hardened plaster material, the first side and second side of each continuous layer of material being substantially covered by the hardened plaster material. In certain such embodiments, each continuous layer of material includes a polymer (e.g., a damping polymer) disposed on a carrier sheet. Another aspect of the disclosure relates to a method for making a plaster board that involves drying a wet body of plaster material while a continuous layer of material or precursor therefor is disposed within it.

The present invention is directed to a construction chemical composition for the preparation of gypsum articles, said construction chemical composition comprising fine calcium sulfate and a dispersant being a polyarylether. Further the present invention is directed to a process for preparing said construction chemical composition as well as an article comprising said construction chemical composition.

Disclosed is a gypsum panel comprising a gypsum core comprising set gypsum and a colloidal material comprising colloidal silica, colloidal alumina, or both.