What are described are the use of a refractory coating composition for production of cores for diecasting, a kit for production of cores for use in diecasting, a method of producing cores for use in diecasting, cores for use in diecasting, and the use of such cores in diecasting, especially of lightweight metals

The additive composition of the present invention is one blended in a sand composition which is subjected to foaming to mold a sand mold, and includes (A) an alkylsulfonate metal salt having an alkyl group with 9 to 22 carbon atoms. The additive composition may further include at least one component selected from a group consisting of (B) an alkylsulfate metal salt, (C) a polyoxyalkylene alkyl ether sulfate metal salt, and (D) an alkylbenzene sulfonate metal salt.

The invention relates to a binder, which contains water glass and further a phosphate or a borate or both. The invention further relates to a method for constructing molds and cores layer by layer, the molds and cores comprising a construction material mixture, which at least comprises a refractory molding base material, and the binder. In order to produce the molds and cores layer by layer in 3-D printing, the refractory molding base material is applied layer by layer and is selectively printed with the binder layer by layer, and consequently a body corresponding to the molds or cores is constructed and the molds or cores are released after the unbonded construction material mixture has been removed.

A description is given of the use of an additive mixture (A) for combination with a solution or dispersion (B) comprising waterglass, for producing a moulding material mixture for producing articles from the group consisting of foundry moulds and foundry cores; a multi-component binder system comprising (A) an additive mixture and (B) a solution or dispersion comprising waterglass; a moulding material mixture comprising a mould base material (C) and also components (A) and (B) of such a multi-component binder system; a method for producing an article from the group consisting of foundry moulds and foundry cores; articles from the group consisting of foundry moulds and foundry cores; and the use of such an article for metal casting, preferably for light metal casting, more particularly for aluminium casting.

Sized molds for metal casting are obtained from molding material mixtures on the basis of inorganic bonding agents containing at least one phosphatic compound and at least one oxidic boron compound, especially sized, water glass-bound forms and cores, having at least one refractory base molding material, water glass as inorganic bonding agent and amorphous particulate silicon dioxide and one or more powdery oxidic boron compounds and one or more phosphatic compounds. The invention furthermore relates to a method for producing sized foundry mold bodies and use thereof, in particular for producing cast parts from iron alloys. The sizing is a water-based sizing.

A method for manufacturing a structure from a granular material, called sand, in particular a mold. A layer of sand is deposited. The layer of sand is selectively agglomerated by spraying, using a spray nozzle, an inorganic binder having an M2SiO3 type (meta)silicate dissolved in a solvent. Prior to the spraying, the inorganic binder is heated to a temperature to confer on it a viscosity less than 0.2 Pa.Math.s. A device for implementing the method is provided.

The present invention describes a coating composition for the foundry industry, for use in the foundry, in particular comprising certain organic ester compounds of a formula (I) and particulate, amorphous silicon dioxide (SiO.sub.2); and also coated foundry molding elements, especially foundry molds and/or foundry cores, which each comprise a coating composition of the invention. The invention further describes the use of a coating composition of the invention for producing a coating on a foundry molding element and a method for producing a foundry molding element coated with a water-containing refractory coating. The invention likewise describes a kit whose contents include a coating composition of the invention.

The present invention describes the use of a coating composition, comprising an aqueous phase having a pH of at most 5 and one or more refractories, in the foundry industry and also coated, waterglass-bound foundry molding elements, especially foundry molds and/or foundry cores, which each comprise such an aforementioned coating composition. The invention further describes a method for producing a coated, waterglass-bound foundry molding element. The invention likewise describes a kit whose contents include an aforementioned coating composition, comprising aqueous acid and one or more refractories.

The present invention refers to a stable sodium and iron silicate solution that has a weight ratio of SiO.sub.2 to Na.sub.2O from 1.5 to 2.5 and a total percentage of solids, expressed by the sum of SiO.sub.2 and Na.sub.2O, from 20% to 55%. Said solution also has a soluble iron content, expressed by Fe, from 0.1% to 7%, and a water content from 38% to 79.9%. The present invention also refers to the process for preparing said stable solution of sodium and iron silicate, which comprises the steps of: (a) providing a siliceous material containing iron; (b) submitting said siliceous material containing iron to a hydrothermal treatment with caustic soda under high temperature and controlled pressure; and (c) filtering said reacted solution to separate the reacted portion of the hydrothermal treatment from the unreacted portion. Additionally, the present invention refers to the uses of said stable sodium and iron silicate solution.

The present invention provides a curing agent for casting a water glass, including an ester and an amorphous silicon dioxide obtained by a thermal decomposition of ZrSiO.sub.4; and the curing agent for casting the water glass does not contain water. According to the present invention, the curing agent for casting the water glass has a strong adhesion-enhancing effect and a long shelf life, and is easy to use.