Abstract: The invention relates to novel metakaolin pigments which are characterized by a unique combination of exceptionally high brightness and exceptionally low abrasion along with the excellent hiding power equal to that achieved by premium conventional calcined kaolin pigments. The invention relates also to a method of producing such metakaolin pigments by subjecting relatively coarse high purity and high crystallinity kaolin booklets to highly intensive media grinding to generate fine kaolin particles of reduced crystallinity, and calcining the ground particles while limiting calcination temperature and time such as to form metakaolin.

Abstract: The present invention relates to a process for reducing the inherent low shear viscosity of kaolin clays contaminated with expandable layer minerals. A water soluble tetraalkyl ammonium compound is contacted with the clay during conventional wet processing.

Abstract: Amine-complexed zinc salts of organic diacids selected from the group consisting of (i) dicarboxylic acids, (ii) diphenols, and (iii) phthalic acids. Specifically disclosed compounds include C.sub.2 -C.sub.3 alkylene diamine-complexed zinc salts of thiodiphenol and sulfonyldiphenol, and ethylene diamine-complexed salts of phthalic, isophthalic and terephthalic acids. Such amine-complexed zinc salts have utility as corrosion inhibitors in coating compositions for metallic substrates, e.g., paints based on alkyds, latexes or linseed oil. Also disclosed are anticorrosion additives, comprising the aforementioned amine-complexed salts distended on mineral fillers such as kaolin, and a method of making same by reaction of zinc oxide, amine, and organic diacid, at elevated temperatures, in an aqueous slurry of the mineral filler. At least the dicarboxylic acid and diphenol derived salts also display utility as inhibitors of marine growth (algae and barnacles) on substrates.

Abstract: A heat stabilized slurry of bulked kaolin pigment is prepared by mixing a small but effective amount of a water-soluble cationic material such as a cationic polyelectrolyte flocculant with a kaolin clay pigment in the presence of water. The resultant bulked clay product is dispersed to form a high solids clay-water slurry useful in making aqueous coating colors suitable for manufacturing lightweight coated publication papers or the pigment can be used as a filler for paper webs. Slurries having stable viscosity during storage at elevated temperature and improved resistance to the formation of sediment are prepared by using as the dispersant a combination of an anionic lignosulfonate and an anionic naphthalene sulfonate formaldehyde complex in combination with a polyacrylate salt.

Abstract: A method for preparing a heat stable aqueous slurry of a bulking pigment suitable for use in coating or filling paper which comprises preparing a fluid aqueous suspension of particles of kaolin clay, adding thereto a water-soluble cationic polyelectrolyte, the amount of said cationic polyelectrolyte being sufficient to substantially thicken and flocculate said fluid suspension, acidifying the resulting flocculate clay suspension, bleaching the clay in said suspension with a hydrosulfite salt, filtering said acidified suspension to recover bulked clay, washing the filtered clay and adding minimal amounts of a sodium polyacrylate and a nonionic surfactant to the recovered bulked clay to provide a fluid suspension of bulked clay.

Abstract: A highly bulked kaolin pigment is prepared by mixing a small but effective amount of a water-soluble cationic polyelectrolyte flocculant with a kaolin clay pigment in the presence of water to prepare a bulked clay pigment product. Upon dewatering, the resultant polyelectrolyte treated clay product can be dispersed to form high solids clay-water slurries useful in making aqueous coating colors suitable for manufacturing coating lightweight publication papers or the pigment can be used as a filler for paper webs.

Abstract: Amine-complexed zinc salts of organic diacids selected from the group consisting of (i) dicarboxylic acids, (ii) diphenols, and (iii) phthalic acids. Specifically disclosed compounds include C.sub.2 -C.sub.3 alkylene diamine-complexed zinc salts of thiodiphenol and sulfonyldiphenol, and ethylene diamine-complexed salts of phthalic, isophthalic and terephthalic acids. Such amine-complexed zinc salts have utility as corrosion inhibitors in coating compositions for metallic substrates, e.g., paints based on alkyds, latexes or linseed oil. Also disclosed are anticorrosion additives, comprising the aforementioned amine-complexed salts distended on mineral fillers such as kaolin, and a method of making same by reaction of zinc oxide, amine, and organic diacid, at elevated temperatures, in an aqueous slurry of the mineral filler. At least the dicarboxylic acid and diphenol derived salts also display utility as inhibitors of marine growth (algae and barnacles) on substrates.

Abstract: A substantially white, anhydrous, amorphous aluminosilicate pigment is obtained by calcining a combination of previously uncalcined kaolin clay and an alumina source. The calcination is carried out at a temperature of about 870.degree. C. to 1400.degree. C., preferably about 870.degree. C. to 1260.degree. C., for a suitable period of time, e.g., 0.1 to 3 hours. The pigments obtained by the foregoing method display enhanced brightness greater than the merely additive brightness which would be obtained by mixing alumina with a previously calcined kaolin clay and are otherwise well suited for use as paper-filling or coating pigments.