The subject matter of the invention is mold material mixtures for producing molds or cores for metal casting, consisting of at least one refractory base mold material, a binder and an additive based on factice. The invention also relates to a component system, a method for producing molds and cores using the mold material mixtures or the component system respectively, and to molds and cores produced by said method.

The present invention relates to the use of closed-pore microspheres of expanded perlite as a filler for producing moldings for the foundry industry, to a composition for producing moldings for the foundry industry, comprising closed-pore microspheres of expanded perlite as a filler, and a binder, the binder being selected from the group consisting of water glass, phenol-formaldehyde resins, two-component systems comprising as reactants a polyisocyanate and a polyol component containing free hydroxyl groups (OH groups), and starch, and also to moldings for the foundry industry and to a process for producing a molding for the foundry industry.

An aggregate mixture for a mold, the aggregate mixture including an aggregate, a water-soluble binder, a water-soluble foaming agent, an aqueous mold release agent, and water.

The present disclosure includes binder systems for making foundry articles. The binder systems may comprise a humic substance-containing component that comprise lignite, an isocyanate component, and a catalyst component. The binder systems may be mixed with an aggregate (e.g., sand) for making foundry articles such as molds and cores. Also disclosed herein are methods of making foundry articles using the binder systems.

A structure for manufacturing castings, containing an inorganic fiber, a layered clay mineral, and an inorganic particle other than the layered clay mineral and having an organic content of 5 mass % or lower or having a mass loss of 5 mass % or lower when heated at 1000 C. for 30 minutes. The inorganic particle preferably contains one or more selected from obsidian, graphite, and mullite. The inorganic fiber preferably contains carbon fiber. The inorganic fiber preferably has an average length of 0.5 to 15 mm. The layered clay mineral preferably contains one or more selected from bentonite and montmorillonite.

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.

The subject matter of the invention is mold material mixtures for producing molds or cores for metal casting, consisting of at least one refractory base mold material, a binder and an additive based on factice. The invention also relates to a component system, a method for producing molds and cores using the mold material mixtures or the component system respectively, and to molds and cores produced by said method.

The invention relates to an aqueous alkaline binder composition for curing with carbon dioxide gas, comprising a negatively charged or uncharged phenol-aldehyde resin, comprising phenol groups, which is selected from the group consisting of resoles and mixtures comprising one or more resoles and also one or more novolacs, an oxyanion selected from the group consisting of borate ions, aluminate ions, stannate ions, zirconate ions, titanate ions, and mixtures thereof, for forming a stable complex with the resole phenol-aldehyde resin, where the total molar amount of the phenol groups of the phenol-aldehyde resin in the aqueous alkaline binder composition is in the range from 1 to 3 mol/kg, based on the total mass of the aqueous alkaline binder composition, and where the phenol-aldehyde resin possesses an average molecular weight (Mw) in the range from 750 to 1200 g/mol, determined by means of gel permeation chromatography. The invention relates, moreover, to a corresponding use, to a molding mixture for producing a foundry molding, and also to a corresponding method for producing a foundry molding, and to a corresponding foundry molding.

The invention relates to an aqueous alkaline binder composition for curing with carbon dioxide gas, comprising a negatively charged or uncharged phenol-aldehyde resin, comprising phenol groups, which is selected from the group consisting of resoles and mixtures comprising one or more resoles and also one or more novolacs, an oxyanion selected from the group consisting of borate ions, aluminate ions, stannate ions, zirconate ions, titanate ions, and mixtures thereof, for forming a stable complex with the resole phenol-aldehyde resin, and one or more silanes in a total amount in the range from 2.5 to 10 wt %, based on the total mass of the binder composition, where the total molar to amount of the phenol groups of the phenol-aldehyde resin in the aqueous alkaline binder composition is in the range from 1 to 3 mol/kg, based on the total mass of the aqueous alkaline binder composition. The invention relates, moreover, to a corresponding use, to a molding mixture for producing a foundry mold, and also to a corresponding method for producing a foundry mold, and to a corresponding foundry mold.

The present invention relates to the use of closed-pore microspheres of expanded perlite as a filler for producing moldings for the foundry industry, to a composition for producing moldings for the foundry industry, comprising closed-pore microspheres of expanded perlite as a filler, and a binder, the binder being selected from the group consisting of water glass, phenol-formaldehyde resins, two-component systems comprising as reactants a polyisocyanate and a polyol component containing free hydroxyl groups (OH groups), and starch, and also to moldings for the foundry industry and to a process for producing a molding for the foundry industry.