Abstract: The invention relates to mold material mixtures for producing molds and cores for metal casting, consisting of at least one refractory material, a binder based on resols and amorphous silicon dioxide. The invention also relates to a multicomponent system and methods for producing molds and cores using the mold material mixtures as well as molds and cores for metal casting produced according to this method.

Abstract: The invention relates to a method for regenerating used foundry sand, which is contaminated with soluble glass, wherein: used foundry sand is provided, which is tainted with a binding agent made of the soluble glass, to which a particle-shaped metal oxide is added; and the used foundry sand is subjected to a thermal treatment, wherein the foundry sand is heated to a temperature of at least 200° C., thereby obtaining regenerated foundry sand. The invention further relates to regenerated foundry sand, as that obtained from using the method.

Abstract: The present invention relates to a polyurethane-based binder using isocyanates containing uretonimine and/or carbodiimide groups for producing cores and casting molds, to a mold material mixture containing the binder, and to a method using the binder for producing casting molds.

Abstract: The invention relates to a method for producing casting moulds and cores, according to which a moulding material mixture consisting of at least one refractory material and water glass as an inorganic binding agent is cured with the aid of a carbonyl compound introduced into the gas phase, or carried with the gas phase. The invention also relates to a corresponding moulding material mixture, to a multi-component system and to moulds and cores produced according to the method.

Abstract: The invention relates to a size composition (coating composition) for casting moulds and cores, comprising at least one metal additive which contains a metal or a compound of a metal, wherein the metal is selected from one of groups 7 or 9 to 12 of the Periodic Table of the Elements. The invention also relates to a process for producing a casting mould, which comprises a mould coating of the size (coating) according to the invention, and to the use of said mould for the casting of metals.

Abstract: The invention relates to a mould material mixture for producing casting moulds for metal processing, a process for producing casting moulds, casting moulds which can be obtained by the process and their use. The production of the casting moulds is carried out using a refractory base moulding material and a binder based on water glass. A proportion of a particulate metal oxide selected from the group consisting of silicon dioxide, aluminium oxide, titanium oxide and zinc oxide is added to the binder, with particular preference being given to using synthetic amorphous silicon dioxide. The mould material mixture contains a surface-active material as further significant constituent. The addition of the surface-active material enables the flowability of the mould material mixture to be improved, which makes it possible to produce casting moulds having a very complicated geometry.

Abstract: The present invention relates to a coating and a method for producing a casting mold. The method provides for castings whereby gas defects are largely or completely suppressed.

Abstract: A binder for mold material mixtures is a four-component material. It contains at least one phenolic resin component, at least one isocyanate component, at least one alkyl/alkenyl benzene and at least one dialkylated and/or dialkenylated naphthalene. The phenolic resin component acts as the polyol component and contains phenolic resin obtainable from the reaction between a phenol compound and an aldehyde compound. The isocyanate component contains at least one polyisocyanate with at least two NCO groups per molecule. The alkyl/alkenyl benzene has a boiling point above 250° C. The dialkylated and/or dialkenylated naphthalene has a boiling point above 270° C.

Abstract: A method for producing cores and molds for the foundry industry utilizing a flowable fire-resistant primary molding material. The method includes an acid applied to the flowable fire resistant primary molding material to obtain an acid-coated fire-resistant primary molding material. A binder that can be cured by acid is applied to the acid-coated fire resistant primary molding material to obtain a fire-resistant primary molding material coated with a binder. The fire-resistant primary molding material coated with a binder is then molded into a molded body, and-the molded body is cured. The acid used is a mixture of methane sulfonic acid and at least one sulfur-free acid. The casting molds can be produced having reduced emission of harmful compounds during casting.

Abstract: A binder system for a molding mixture has at least one phenolic resin component, at least one isocyanate component and at least one solvent component, where the at least one solvent component is a cyclic formal, also known as a cyclic formaldehyde, with or without additional solvents. The phenolic resin component is prepared by reacting a phenol compound with an aldehyde compound. The isocyanate component has at least polyisocyanate that has at least two isocyanate groups per molecule. In the molding mixture, the binder is combined with a refractory molding material.

Abstract: The invention relates to a molding material mixture for production of molded products for the foundry industry, comprising at least one fire-resistant base molding material and a polyurethane-based binder system comprising a polyisocyanate component and a polyol component. According to the invention, the polyurethane-based binder system comprises a portion of a carboxylic acid diester of a branched alkane diol, said portion being at least 3 weight-%, and a portion of aromatic solvent of less than 10 weight-% of the binder system. A preferable carboxylic acid diester is 2,2,4-trimethyl-1,3-pentandiol-diisobutyrate. The molded products produced from the molding material mixture for the foundry industry are characterized by a high strength and a lower generation of fumes and smoke during pouring.

Abstract: A binder for mold material mixtures is a four-component material. It contains at least one phenolic resin component, at least one isocyanate component, at least one alkyl/alkenyl benzene and at least one dialkylated and/or dialkenylated naphthalene. The phenolic resin component acts as the polyol component and contains phenolic resin obtainable from the reaction between a phenol compound and an aldehyde compound. The isocyanate component contains at least one polyisocyanate with at least two NCO groups per molecule. The alkyl/alkenyl benzene has a boiling point above 250° C. The dialkylated and/or dialkenylated naphthalene has a boiling point above 270° C.

Abstract: The present invention relates to a polyurethane-based binder using isocyanates containing uretonimine and/or carbodiimide groups for producing cores and casting molds, to a mold material mixture containing the binder, and to a method using the binder for producing casting molds.

Abstract: The invention relates to a casting mould for the casting of metals, wherein a layer consisting of a material which absorbs harmful substances on at least sections of gas outlet surfaces of the casting mold, in particular the top side thereof. The invention also relates to a coating composition, to a process for producing the casting mold and to the use thereof for casting of metals.