Abstract: This invention relates to a composition suitable for use in making moisture resistant gypsum products. In particular, this invention relates to resin dispersions and their use in combination with gypsum to form moisture resistant gypsum compositions which are settable by hydration. Further, the invention relates to moisture resistant products formed from such settable gypsum compositions, e.g. panels and boards, and a method for the manufacture of such moisture resistant gypsum products.

Abstract: An improved safety collar (10) for a manway system (24) provides a tapered component for guiding the collar into an aperture of a manway lid (28), thus preventing the collar from snagging an edge of the aperture and holding the lid in an open position. The safety collar is defined by an annular wall with a smooth outer surface (12) and a threaded inner surface (14). A chamfered rim (16) of the collar presents an annular sloping surface (18) generally sloping inwardly and upwardly from the outer surface to the inner surface. When the collar is threaded onto a bolt (66) of the bolt assembly, the chamfered rim (16) of the collar guides the collar into an aperture (58) of the manway lid, such as when the lid is lowered into position against a base (26) of the manway system.

Abstract: The present invention is directed to an apparatus and a method for monitoring the viscoelastic properties, of a liquid film (e.g. coating). The apparatus includes a substrate for supporting a liquid film and a T-bar probe that is partially submerged in the liquid film. The apparatus is designed to be attached to a conventional rheometer equipped with a means for effecting relative movement between the probe and the substrate and means for monitoring the resistance to movement of the probe in contact or partially submerged in the film to obtain a measurement of the solidification properties of the liquid film. This apparatus and method are particularly useful in comparing the effects of film formers, viscosity modifiers, solvents, and minerals on the drying rate of coatings at the early stage of film formation.

Abstract: The present invention is directed to an apparatus and a method for monitoring the viscoelastic properties, of a liquid film (e.g. coating). The apparatus comprises a substrate supporting a liquid film, a probe to contact the liquid film, means for effecting relative movement between the probe and the substrate and means for monitoring the resistance to movement of the probe in contact with the film to obtain a measurement of the solidification properties of the liquid film. This apparatus and method are particularly useful in comparing the effects of film formers, viscosity modifiers, solvents, and minerals on the drying rate of coatings at the early stage of film formation.