Abstract: Coated sand cores containing a boronated aluminum phosphate binding agent are used in the production of die castings having undercut regions because of the favorable combination of shakeout properties, resistance to washout, and resistance to surface penetration.

Abstract: A process is provided for the manufacture of titanium compounds and particularly titanium dioxide wherein excess titaniferous bearing material is reacted with dilute sulfuric acid having a concentration of between about 25% and about 60% by weight at a temperature below about 140.degree. C., and in the presence of a reducing agent which affects the reduction of ferric iron to ferrous iron. Thereafter, the titanium sulfate may be recovered or further processed to provide titanium dioxide hydrate accompanied by recycling the spent acid for reaction with the titaniferous bearing material charged to the process. The titanium hydrate may be calcined to provide titanium dioxide.

Abstract: A process is provided for the manufacture of titanium compounds and particularly titanium dioxide wherein excess titaniferous bearing material is reacted with dilute sulfuric acid having a concentration of between about 25% and about 60% by weight at a temperature below about 140.degree. C. Thereafter, the titanium sulphate may be recovered or processed to provide titanium dioxide hydrate accompanied by recycling the spent acid for reaction with the titaniferous bearing material charged to the process. The titanium hydrate may be calcined to provide titanium dioxide pigment.

Abstract: A process is disclosed for preparing a slurry of titanium dioxide having a solids content of at least 60%. In the past titanium dioxide pigment slurries have been prepared by mixing titanium dioxide powder, water and additives in a batch mixer, however, this is a lengthy process and generally results in some agglomeration of the particles. The present process comprises the steps of mixing titanium dioxide pigment, at least one dispersant additive and water to a first mixture having a solids content of at least about 60%, pumping the first mixture through a disperser mill to produce a second mixture free from agglomerates.

Abstract: The present invention is directed to improved separatory devices employing polyurethane forming compositions, such as hollow fiber separatory devices intended to be used in biomedical applications. The separatory device employs at least one separatory membrane, suitable for the intended end use application, which is secured, potted or sealed in a housing using a cured polyurethane composition. The improvement comprises utilizing as the potting agent a polyurethane composition comprising the reaction product of an NCO-terminated prepolymer and a hydroxy terminated lactone derived polyester. The lactone polyester comprises the reaction product of a lactone such as caprolactone, and a polyol such as 1,6-hexane diol. The lactone derived polyester imparts to the polyurethane-forming composition a desirable balance of properties, including low mix viscosity, high reactivity, i.e., low gel and demold times, and acceptable hardness values, when used as a potting agent in biomedical separatory devices.

Abstract: Process of extracting titanium values from titaniferous bearing material by circulating a reaction mixture containing titanium values in an agitation column located within a reaction vessel in a direction countercurrent to the flow of the reaction mixture in the annular space located between the agitation column and the inner reaction vessel wall, said circulation being done in a manner to maintain the titaniferous bearing material in a continuous turbulent suspension flow in the agitation column and discharging the reaction mixture from the reaction vessel and recovering the extracted titanium values.

Abstract: A process is provided for the manufacture of a stable titanyl sulfate solution by diluting a reaction mixture containing iron sulfate and titanyl sulfate with a material selected from water, a titanyl sulfate solution, and mixtures thereof. The titanyl sulfate solution may be recovered or processed to provide titanium dioxide hydrate which may be calcined to provide titanium dioxide pigment.