Abstract: The invention relates to a process for the preparation of a hardening accelerator composition by reacting a calcium source selected from calcium hydroxide, calcium oxide with a water-soluble silicate compound in the presence of at least one water-soluble polymeric dispersing agent and the hardening accelerator composition obtainable by said process. The composition has a low content of anions and of alkali cations and is therefore broadly applicable in building material mixtures.

Abstract: The invention concerns a process for the preparation of a hardening accelerator composition by reaction of a water-soluble calcium compound with a water-soluble silicate compound, said reaction being carried out in the presence of an aqueous solution which contains a water-soluble comb polymer suitable as a plasticizer for hydraulic binders, wherein the water-soluble comb polymer is present as a copolymer which is produced by free radical polymerization in the presence of a phosphorylated monomer and a (meth)acrylic acid ester based polyether macromonomer.

Abstract: Process for the preparation of a sprayable hydraulic binder composition containing as main components water, aggregates, hydraulic binder, set accelerator, characterized in, that a calcium silicate hydrate (C—S—H) containing component is added before and/or at the spray nozzle.

Abstract: The invention concerns a process for the for the preparation of a hardening accelerator composition by reaction of a water-soluble calcium compound with a water-soluble silicate compound, the reaction being carried out in the presence of an aqueous solution which contains a plasticizer suitable for hydraulic binders, characterized in that said reaction is being carried out in the presence of apatite and that the molar ratio of calcium to phosphor in the hardening accelerator is from 25/1 to 400/1.

Abstract: The invention concerns a process for the preparation of a hardening accelerator composition by reaction of a water-soluble calcium compound with a water-soluble silicate compound and by reaction of a calcium compound with a silicon dioxide containing component under alkaline conditions, in both cases the reaction being carried out in the presence of a polycondensate containing at least one structural unit consisting of an aromatic or heteroaromatic moiety bearing a polyether side chain and at least one structural unit consisting of an aromatic or heteroaromatic moiety bearing at least one phosphoric acid ester group and/or its salt. The invention concerns a composition of calcium silicate hydrate and the polycondensate, its use as hardening accelerator and for the reduction of the permeability of hardened compositions.

Abstract: The invention relates to a process for producing calcium sulphate dihydrate by reacting a water-soluble calcium compound with a water-soluble sulphate compound in the presence of water and a polymer containing acid groups, wherein the polymer containing acid groups comprises specific polyether groups. Additionally disclosed are calcium sulphate dihydrate producible by the process according to the invention, and the use thereof for production of gypsum plasterboard.

Abstract: The invention concerns a process for the preparation of a hardening accelerator composition by reaction of a water-soluble calcium compound with a water-soluble silicate compound and a process for the preparation of a hardening accelerator composition by reaction of a calcium compound with a silicon dioxide containing component under alkaline conditions, in both cases the reaction of the water-soluble calcium compound with the water-soluble silicate compound being carried out in the presence of an aqueous solution which contains a water-soluble comb polymer suitable as a plasticizer for hydraulic binders. The invention concerns also a composition of calcium silicate hydrate and comb polymer, its use as hardening accelerator and for the reduction of the permeability of hardened compositions.

Abstract: The invention concerns a process for the preparation of a hardening accelerator composition by reaction of a water-soluble calcium compound with a water-soluble silicate compound and by reaction of a calcium compound with a silicon dioxide containing component under alkaline conditions, in both cases the reaction being carried out in the presence of an aqueous solution of a water-soluble polymer, which contains sulphonic acid and/or sulphonate groups and aromatic groups. The invention concerns also the reaction product of said processes and its use as hardening accelerator for building materials.

Abstract: The invention concerns a process for the preparation of a hardening accelerator composition by reaction of a water-soluble calcium compound with a water-soluble silicate compound and by reaction of a calcium compound with a silicon dioxide containing component under alkaline conditions, in both cases the reaction being carried out in the presence of a polycondensate containing at least one structural unit consisting of an aromatic or heteroaromatic moiety bearing a polyether side chain and at least one structural unit consisting of an aromatic or heteroaromatic moiety bearing at least one phosphoric acid ester group and/or its salt. The invention concerns a composition of calcium silicate hydrate and the polycondensate, its use as hardening accelerator and for the reduction of the permeability of hardened compositions.

Abstract: Process for the preparation of a sprayable hydraulic binder composition containing as main components water, aggregates, hydraulic binder, set accelerator, characterized in, that a calcium silicate hydrate (C—S—H) containing component is added before and/or at the spray nozzle.

Abstract: The invention concerns a process for the preparation of a hardening accelerator composition by reaction of a water-soluble calcium compound with a water-soluble silicate compound and a process for the preparation of a hardening accelerator composition by reaction of a calcium compound with a silicon dioxide containing component under alkaline conditions, in both cases the reaction of the water-soluble calcium compound with the water-soluble silicate compound being carried out in the presence of an aqueous solution which contains a water-soluble comb polymer suitable as a plasticizer for hydraulic binders. The invention concerns also a composition of calcium silicate hydrate and comb polymer, its use as hardening accelerator and for the reduction of the permeability of hardened compositions.

Abstract: The use of a setting accelerator composition for inorganic binders which comprises at least one water-soluble comb polymer suitable as a superplasticizer for hydraulic binders and calcium silicate hydrate particles in the development, exploitation and completion of underground mineral oil and natural gas deposits and in deep wells is proposed. The use according to the invention not only accelerates the setting and hardening of the cement slurries but also shortens the time in which the static gel strength of the hardening cement slurries increases from 100 lb/100 ft2 (4.88 kg/m2) to 500 lb/100 ft2 (24.4 kg/m2).

Abstract: A process for the preparation of a hardening accelerator composition by reaction of a water-soluble calcium compound with a water-soluble silicate compound, said reaction being effected in the presence of a water-soluble dispersant having at least one polyalkyleneglycol structural unit with a functional group at one end of the polyalkyleneglycol, being able to interact as an anchor group with the surface of cement particles, the hardening accelerator composition and its use.

Abstract: The invention concerns a method for accelerating setting of a hydraulic mineral binder composition with added adjuvant including hydrophilic functions. The invention also concerns a composition of hydraulic mineral binders obtainable by said method to accelerate setting. The invention further concerns the use of said hydraulic mineral binder composition in the building industry, civil engineering or oil industry.