Abstract: Disclosed are amorphous silica or silica-alumina spherical particles composed of X-ray diffractometrically substantially amorphous silica or silica-alumina, wherein individual particles have a definite spherical shape and a notched surface, the circularity (A) represented by the following formula: ##EQU1## wherein r1 stands for the radius of the circumcircle of the profile of the particle in an electron microscope photo thereof and r2 stands for the radius of the inscribed circle of the profile of the particle in the electron microscope photo, is in the range of from 0.90 to 1, the notching degree (B) represented by the formula: ##EQU2## wherein .DELTA.t stands for the depth between the peak and trough in the radial direction of notches on the profile of the particle in the electron microscope photo and r1 is as defined above, is in the range of from 1 to 10%, and the primary particle size (2r1) determined by the electron microscope method is in the range of from 0.1 to 20 .mu.m.

Abstract: Disclosed is an alumina-silica resin additive consisting of amorphous alumina-silica particles in which a definite cubic or spherical shape is retained in primary particles and the particle sizes of both the primary particles and the secondary particles are controlled to very small values. This additive is excellent in dispersibility in a resin, non-blowing property, slip characteristic and anti-blocking property. A product obtained by surface-treating the amorphous alumina-silica particles with a certain amount of an organic lubricant is very valuable as a filler.

Abstract: The invention is a process for preparing amorphous silica alumina spherical particles by mixing sodium silicate or silicic acid gel with sodium aluminate and sodium hydroxide in an aqueous solution to form a gel, homogenizing the formed gel, crystallizing this intermediate product at 85.degree. C. to 200.degree. under atmospheric pressure or under hydrothermal conditions to form spherical zeolite particles with an x-ray diffraction pattern inherent to P-type zeolites and with a notched surface, treating the zeolite particles with acid to remove the sodium, thereby rendering the particles amorphous.

Abstract: Disclosed are amorphous silica or silica-alumina spherical particles composed of X-ray diffractometrically substantially amorphous silica or silica-alumina, wherein individual particles have a definite spherical shape and a notched surface, the circularity (A) represented by the following formula: ##EQU1## wherein r1 stands for the radius of the circumcircle of the profile of the particle in an electron microscope photo thereof and r2 stands for the radius of the inscribed circle of the profile of the particle in the electron microscope photo, is in the range of from 0.90 to 1, the notching degree (B) represented by the following formula: ##EQU2## wherein .DELTA.t stands for the depth between the peak and trough in the radial direction of notches on the profile of the particle in the electron microscope photo and r1 is as defined above, is in the range of from 1 to 10%, and the primary particle size (2r1) determined by the electron microscope method is in the range of from 0.1 to 20 .mu.m.

Abstract: Active analcime having a chemical composition comprising 60 to 95% by weight of SiO.sub.2, 0.3 to 20% by weight of Al.sub.2 O.sub.3 and 0.02 to 11% by weight of Na.sub.2 O based on the three components, an X-ray diffraction pattern inherent to analcime and a moisture adsorption of 5 to 30% by weight as determined under conditions of a relative humidity of 90%, an ambient temperature of 25.degree. C. and a standing time of 24 hours, wherein individual particles have a tetracosahedral or angle-rounded tetracosahedral particulate shape and the primary particle size of 0.1 to 50 .mu.m as determined according to the electron microscope method. This active analcime is obtained by acid-treating a zeolite by using an acid in an amount of 0.1 to 1.2 molar equivalents per mole of the sum of Al.sub.2 O.sub.3 and Na.sub.2 O components in the zeolite so that the crystal structure of analcime is left.

Abstract: Disclosed to a stabilizer composition for a chlorine-containing polymer, which comprises a zeolite type stabilizer; calcium hydroxide or magnesium hydroxide, a metal soap type stabilizer and perchloric acid as indispensable components.The stabilizer composition is obtained by adding a metal soap type stabilizer to a mixture of a zeolite type stabilizer and calcium hydroxide or magnesium hydroxide under attrition to cover the mixture with the metal soap type stabIlizer at a high efficiency, and adding perchloric acid to the covered mixture.In the stabilizer composition of the present invention, the initial discoloration, which is a fatal defect of the conventional zeolite type stabilizer for a chlorine-containing polymer, can be prevented, and a sufficient hydrogen chloride-capturing capacity is exerted and a high heat stability is attained without occurrence of bleeding.

Abstract: An inorganic filler composed of a modified montmorillonite group clay mineral and having an X-ray diffraction pattern inherent to montmorillonite, an oil absorption of at least 100 ml/100 g and a Hunter whiteness of at least 80%. The modified clay mineral is produced by reacting a clay mineral of the montmorillonite group which 10 to 200% by weight based on the dry weight of the mineral, of an alkaline earth metal hydroxide in the presence of water, and reacting the reaction product with a salt of a metal of Group IIb, III or IV of the periodic table containing an acid radical which gives a soluble alkaline earth metal salt upon reaction. The inorganic filler is especially suitable for use in lightweight paper.

Abstract: Disclosed is a process for the preparation of a zeolite slurry being excellent in either the static stability or the dynamic stability and having a good flowability, which comprises neutralizing an aqueous cake or slurry containing water and zeolite in such a state that both are substantially inseparable from each other by filtration, with an inorganic or organic acid or an acid anydride or acidic salt thereof so that the pH value of the zeolite slurry at the time of completion of addition of said acid, acid anhydride or acidic salt is in the range of from 9.5 to 12 and the pH value of the zeolite slurry in the stationary state after addition of said acid, acid anhydride or acidic salt is in the range of from 11.3 to 12.7, adding a water-soluble or water-dispersible organic polymeric dispersant in an amount of at least 0.1% by weight based on the anhydrous zeolite to the neutralized zeolite slurry, and subjecting the resulting slurry to highly shearing stirring.