摘要:
The invention provides water repellent compositions comprising a wax and a styrene (meth)acrylic copolymer comprising at least some active hydrogen; water resistant objects such as gypsum objects comprising the water repellent compositions and processes for forming water resistance objects using the water repellent compositions.
摘要:
Papier composite particulierement adapte a une utilisation en tant que feuille de couverture dans la production de plaques de cloison de gypse ou platre, le papier etant suffisamment poreux pour permettre un meilleur drainage et un sechage plus rapide au cours de la production du papier, et lorsqu'il est applique sur les surfaces d'un platre de formation d'un panneau de cloison, il permet une utilisation reduite de la chaleur dans la conversion de la plaque de cloison, economisant ainsi de l'energie dans la production des panneaux pour le sechage de ces derniers. Le papier comprend, en pourcentage en poids: (A) des fibres en une quantite superieure a 65% jusqu'a environ 90% et ayant une liberte de fibre de 350 a 550 ml environ d'apres le systeme 'Canadian Standard Freeness', (B) un materiau mineral de remplissage en une quantite superieure a 10% jusqu'a environ 35%, (C) un liant en une quantite de 1% environ jusqu'a 3-1/2% environ, (D) un agent de floculation en une quantite de 2 environ jusqu'a 4 1b./tonne environ, et (E) un agent d'appretage en une quantite effective empechant la penetration de l'eau. Dans un mode preferentiel de realisation, le papier est traite avec un agent d'appretage interieur pendant sa formation, puis il est traite avec un agent d'appretage superficiel apres sa formation, de maniere a obtenir une meilleure adhesion sur le noyau de gypse. Les figures 3 et 4 montrent l'effet du CaCO3 sur la porosite et la longueur de cassure du papier.
摘要:
A gypsum board having face and back cover sheets, a board core disposed between the face and back cover sheets, the core having set gypsum formed from a core slurry of water and stucco, a back skim coat layer defining first and second skim coat faces, the back skim coat formed from a back skim coat slurry of water, stucco, and a skim coat intumescent material, the back skim coat disposed in bonding relation to the core, the first face of the skim coat layer facing the back cover sheet, and the second face of the skim coat layer facing the board core, and the gypsum board having a High Temperature Shrinkage (S) of about 10% or less in the z direction when heated to about 1560 °F (850 °C), according to ASTM C1795-15.
摘要:
Disclosed are a composite gypsum board and a method of preparing gypsum board. The board contains at least one set gypsum layer sandwiched between face and back cover sheets. The set gypsum layer is formed from at least stucco and water. The stucco material generally includes a high salt impurity content, for example, when the stucco is calcined from certain sources of low-quality synthetic gypsum. For example, in some embodiments, the salts are chloride salts, e.g., sodium chloride (NaCl), potassium chloride (KCl), magnesium chloride (MgCl2), and/or calcium chloride (CaCl2). The board and methods improve the bond between the gypsum layer(s) and at least one of the cover sheets (e.g., the back cover sheet). Also provided are methods and systems relating to drying gypsum board.
摘要:
Disclosed is a composite gypsum board comprising a board core comprising set gypsum sandwiched between face and back cover sheets. The composite gypsum board also comprises an intermediate sheet between the board core and the face cover sheet, with a thin, dense gypsum layer disposed between the intermediate sheet and the face cover sheet. Optionally, a second dense gypsum layer can be disposed between a first major side of the board core and the back cover sheet. Also disclosed is a method of preparing a composite gypsum board in which an intermediate sheet is applied over a dense gypsum layer disposed on a face cover sheet. A back cover sheet is applied to the other major side of the board core, with a second dense gypsum layer optionally disposed therebetween.
摘要:
The invention concerns an apparatus for furnishing a liner with a layer of stucco slurry, comprising at least: - a conveying device (24) for conveying a liner (7), said conveyor device defining a transport direction (31); - a stucco slurry feeder device (26) for casting stucco slurry onto the liner (7); - a stucco slurry distribution device (27) for distributing stucco slurry cast onto the liner (7); and - at least one stripper device (28) for stripping stucco slurry from lateral portions of the liner. The invention further concerns a method for furnishing a liner with a layer of stucco slurry of defined width and a method for producing a gypsum plasterboard.
摘要:
A paper based overlay is provided. The overlay has a paper impregnated with a resin composition having an acrylic resin having a glass transition temperature in a range of from about -20 °C to about 40 °C and a resin content from about 15 to about 35 wt. % based on the weight of the overlay. The acrylic composition may include wax in the amount of about 0.005 to about 3.5 wt.% based on the weight of the resin composition. A method of producing the overlay is also provided. The overlay is highly water and abrasion resistant with low volatile content.
摘要:
A gypsum board provided with a foamed gypsum core layer, a facing sheet over the foamed gypsum core, and a latex polymer coating layer on an outer surface of the facing sheet. The latex polymer having a glass transition temperature (Tg) of 0 to 35° F. Methods for making the board are also disclosed.
摘要:
Provided are wallboards in which gypsum core is adhered to a paper cover sheet with an adhesive. Wallboards with laminated paper cover sheets in which an inner water-absorbent cover sheet is adhered to the outer paper cover sheet are provided as well. Methods for making these wallboards are provided as well.
摘要:
Verfahren zur Herstellung einer Gipsplatte, mit den Schritten Formen eines Gipskerns aus einer Stuckgips-Slurry, Bereitstellen eines Papiers oder Kartons, Herstellen einer Gipsplatte aus dem Gipskern und dem Papier oder Karton, wobei die die Gipsslurry ummantelnden Kartonbahnen stuckgipsgesättigtes Wasser aus der Gipsslurry aufsaugen und sich hierbei die im Karton befindlichen Stuckgipskörner unter Ausbildung von „Linker-Kristallen" in Caiciumsulfat-Dihydrat umwandeln, wobei parallel hierzu Caiciumsulfat-Dihydrat aus der stuckgipsgesättigten Lösung kristallisiert und wobei die sich im Karton ausbildenden Linker-Kristalle als Kristallisationskeime fungieren.