Abstract: A method and system for producing a gypsum product comprising a mixer for mixing gypsum and water and two foam feeds into the system wherein the foam feeds each comprise foam of different bubble size distributions.

Abstract: A gypsum board has two opposed faces, and a fibrous mat being embedded in one of the faces of the board. The fibrous mat comprises fibres that are bound by a polymeric binder. The length of the fibres is greater than 20 mm, and the diameter is greater than 14 micron. The polymeric binder is substantially formaldehyde-free. The fibrous mat achieves fire resistance in the gypsum board without the need to incorporate flame retardants into the binder, as well as providing flexural strength.

Abstract: The invention provides a calcium sulphate-based product comprising a phosphate as additive for increased fire resistance. Particularly preferred phosphate additives may be those containing aluminum or ammonium ions.

Abstract: A method of forming a gypsum based product is disclosed. The method comprises the steps of: calcining a mixture of water and gypsum under conditions of raised temperature and pressure within a vessel to produce an alpha-hemihydrate slurry therein; passing the alpha-hemihydrate slurry from the vessel to a mixer for mixing with additional water to produce a settable slurry, which is arranged to set to form the gypsum based product.

Abstract: A panel for use in building construction comprises a plasterboard having two opposed faces, a polymer-based lamina being provided on one of these faces. The weight per unit area of the panel lies in the range 13.5 to 17.5 kg/m2, and the thickness of the panel lies in the range 11-25 mm.

Abstract: A drier for drying boards (32) comprises at least one conduit (34, 40) for directing airflow towards one of the faces of the board (32). The drier is configured such that at least a portion of the airflow travels across the face of the board (32) along the longitudinal axis of the drier, the longitudinal axis of the drier being the axis along which the board (32) travels as it is dried.

Abstract: This disclosure relates to using polyester films on building boards to enable improved surface coatings. The polyester film is preferably applied to a glass mat via an adhesive to form a laminate. This laminate is then bonded to the exterior surface of a gypsum board. The polyester film is advantageous because it allows for exterior surface coatings to be applied. In one embodiment, an exterior acrylic coating is applied to the polyester film. Boards constructed in accordance with this disclosure allow for exterior finishings to be achieved without the need for excessive finishing materials or steps.

Abstract: Disclosed is a building board construction with increased surface strength. More specifically, increased nail pull strength is achieved via the application of an external surface coating. The surface coating is ideally applied to a paper faced gypsum building board. In one possible embodiment, the coating is formed from a water soluble polymer.

Abstract: Disclosed is a building board construction with increased surface strength. More specifically, increased nail pull strength is achieved via the application of an external surface coating. The surface coating is ideally applied to a paper faced gypsum building board. In one possible embodiment, the coating is formed from a water soluble polymer.

Abstract: A building product comprises calcium sulphate dihydrate particles bound by an organic binder. The calcium sulphate dihydrate particles each have a longest dimension and a lateral dimension, wherein the lateral dimension corresponds to the maximum breadth of the particle about the axis defined by the longest dimension. The calcium sulphate dihydrate particles have a low aspect ratio such that for at least 75% of the calcium sulphate dihydrate particles, the value of the lateral dimension is at least 20% of the value of the longest dimension.

Abstract: A pressing assembly (10) and a method for forming a depression (105) within a moving, wet gypsum board (100) is disclosed. The assembly comprises a pressing head (16) comprising a pressing surface which is arranged to contact the board, and a support member (17), the pressing head (16) being arranged to compress a portion of the board between the pressing surface and the support member (17) to form a depression (105) within the board (10). The pressing surface comprises a first and second surface portion (24, 25) separated by a relief portion (27), which is arranged to press the board (100) toward the support head (17) with less compressive force than the first and second surface portion (24, 25).

Abstract: A panel for use in building construction comprises a substrate board having two opposed faces. A lamina is secured to a first one of the faces of the substrate board by means of one or more regions of bonding between the lamina and the board. The one or more regions of bonding cover a total area that is less than 20% of the total interfacial area between the lamina and the board.

Abstract: A method and system for producing a gypsum product comprising a mixer for mixing gypsum and water and two foam feeds into the system wherein the foam feeds each comprise foam of different bubble size distributions.

Abstract: An actuator for controlling the operation of an apparatus comprises a panel (16) and an acoustic sensor (26). The panel provides a partition within a building structure, while the acoustic sensor is adapted to detect acoustic waves propagating through the panel. When a user exerts pressure against the panel, the sensor detects the acoustic waves that are formed and emits signals for controlling the operation of an apparatus, such as a doorbell, a light source, a television, a sound system, a ventilation system, a window blind, a radio or an alarm.

Abstract: The invention provides a calcium sulphate-based product comprising a phosphate as additive for increased fire resistance. Particularly preferred phosphate additives may be those containing aluminium or ammonium ions.