The present invention relates to a catalyst system comprising a transition metal compound on a solid carrier which is a surface-reacted calcium carbonate. The invention further relates to a method for manufacturing said catalyst system and to its use in heterogeneous catalysis.

The purpose of the present invention is to provide: a composite pigment, and production method thereof, which can suppress luster of a coating film by modifying an inorganic coloring pigment, and which can be used in various applications such as low-gloss (luster reduction effect) pigments and matte pigments; a paint composition which can achieve both an excellent coating film texture and also the property of having low gloss and luster even when added to a coating film; and a coating film. In this composite pigment, the inorganic coloring pigment is fixed by an inorganic compound, and a plurality of particles of the inorganic coloring pigment are aggregated into granular form through the inorganic compound.

The purpose of the present invention is to provide a composite pigment which can be dispersed and made into paint in a manner that saves labor compared with conventional flat emulsion paints, and which can achieve concealing properties and low glossiness (a luster reduction effect) without separately adding a matting agent. This composite pigment contains an inorganic compound and/or an organic compound, and a fixed extender pigment.

The present invention relates to a process for the preparation of a surface-reacted precipitated calcium carbonate (PCC) pigment having an insoluble, at least partially crystalline calcium salt on its surface. In the process of the present invention, a PCC containing pigment is contacted with H.sub.3O.sup.+ ions and a solubilized anion in an aqueous medium in the presence of excess solubilized calcium ions to form the surface-reacted PCC having an insoluble, at least partially crystalline calcium salt of the anion formed on its surface.

A process of producing a surface-reacted calcium carbonate is described. In embodiments, a calcium carbonate-comprising material is treated with at least one H.sub.3O.sup.+ ion donor, carbon dioxide, and at least one water-soluble metal cation source in an aqueous medium to form an aqueous suspension of surface-reacted calcium carbonate. A surface-reacted calcium carbonate obtained by said process and its use are also described.

The present invention relates to a composition comprising a first component being an inorganic mineral or mineral-like material having a porous structure, and a second component being a hygroscopic compound; a process for preparing such a composition; a composite material comprising a such a composition; a product comprising such a composition and/or composite material as well as a use of such a composition and/or a composite material as a flame retardant or as a humidity adjusting agent.

The present invention relates to a process for the preparation of a surface-reacted precipitated calcium carbonate (PCC) pigment having an insoluble, at least partially crystalline calcium salt on its surface. In the process of the present invention, a PCC containing pigment is contacted with H.sub.3O.sup.+ ions and a solubilized anion in an aqueous medium in the presence of excess solubilized calcium ions to form the surface-reacted PCC having an insoluble, at least partially crystalline calcium salt of the anion formed on its surface.

The present invention refers to a process for preserving an aqueous preparation of mineral material like e.g. calcium carbonate preparations, and to the use of a composition as a preservative in an aqueous preparation of mineral materials.

The present invention refers to a process for preserving an aqueous preparation of mineral material like e.g. calcium carbonate preparations, and to the use of a composition as a preservative in an aqueous preparation of mineral materials.

The invention relates to a material comprising at least 97% by weight alkaline earth metal carbonates having a calcium oxide content of 0.3% by weight or less and a particle size group of 0.1 to 1.8 mm. The invention furthermore relates to a method for the preparation thereof and also the use thereof for deacidification, filtration and/or hardening of liquids.