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.

A foundry mix includes a major amount of a foundry aggregate and an effective binding amount of a binder system. The binder system cures in the presence of sulfur dioxide and a free radical initiator. The binder system may include (1) 10 to 70 parts by weight of an epoxy novolac resin; (2) 0.5 to 10 parts by weight of resorcinol; (3) 20 to 70 parts by weight of a monomeric or polymeric acrylate; and (4) an effective amount of a free radical initiator. Notably, (1), (2), (3) and (4) are separate components or mixed with another of said components, provided (4) is not mixed with (3), where said parts by weight are based upon 100 parts of the binder system.

The present invention relates to a phenolic resin for use in the phenolic resin component of a two-component binder system for the polyurethane cold box process, to a two-component binder system for use in the polyurethane cold box process, to a molding material mixture for curing by contacting with a tertiary amine, to the use of a corresponding phenolic resin, of a corresponding phenol component, of a corresponding two-component binder system or of a corresponding molding material mixture. The present invention relates, moreover, to an article from the group consisting of feeders, foundry molds and foundry cores, producible from a corresponding molding material mixture, to a process for preparing a phenolic resin, and to a process for producing an article from the group consisting of feeders, foundry molds and foundry cores.

Casting of non-ferrous metals, especially aluminum and magnesium, can have problems with erosion, in which molten metal contacts the mold or core surfaces during the pouring process, resulting in the sand being dislodged. Binder systems addressing this issue often use bisphenol F epoxy resin. A binder system is provided in which a major portion of the epoxy resin component is a bisphenol epoxy resin that has been modified by incorporating oxazolidone rings into an epoxy backbone of the bisphenol epoxy resin, especially a bisphenol A epoxy resin. The modification is preferably achieved by reacting the diglycidyl ether of the bisphenol with a methylene diphenyl diisocyanate.

The object of the invention is a component system for producing a binder for metal casting on the basis of phenolic resins of the benzyl ether type and isocyanates containing non-polar solvents.

A foundry mix includes a major amount of a foundry aggregate and an effective binding amount of a binder system. The foundry binder system cures in the presence of sulfur dioxide and a free radical initiator. The binder system may include (1) 10 to 70 parts by weight of an epoxy novolac resin; (2) 0.5 to 10 parts by weight of resorcinol; (3) 20 to 70 parts by weight of a monomeric or polymeric acrylate; and (4) an effective amount of a free radical initiator. Notably, (1), (2), (3) and (4) are separate components or mixed with another of said components, provided (4) is not mixed with (3) until a foundry mix is to be created, where said parts by weight are based upon 100 parts of the binder system.

A foundry mix includes a major amount of a foundry aggregate and an effective binding amount of a binder system. The binder system cures in the presence of sulfur dioxide and a free radical initiator. The binder system may include (1) 10 to 70 parts by weight of an epoxy novolac resin; (2) 0.5 to 10 parts by weight of resorcinol; (3) 20 to 70 parts by weight of a monomeric or polymeric acrylate; and (4) an effective amount of a free radical initiator. Notably, (1), (2), (3) and (4) are separate components or mixed with another of said components, provided (4) is not mixed with (3) until a foundry mix is to be created, where said parts by weight are based upon 100 parts of the binder system.

Provided are a binder in the producing of a casting sand mold according to an ink jet type lamination shaping method in which a binder is printed with respect to sand, a method for producing the binder, and a method for producing a casting sand mold using the binder. Specifically, provided are a binder useful for a casting sand mold of an ink jet type, containing: a resol-type phenolic resin that is obtained by reacting aldehydes (A1), phenols (P1), and a compound (N) having two or more phenolic hydroxyl groups in one molecule or by reacting the aldehydes (A1) and a novolac-type phenolic resin (N1), in the presence of an alkali catalyst, and has a dispersion degree (Mw/Mn) of 1.0 to 3.5 and a phenolic monomer residue of 5% or less, a method for producing the binder, and a method for producing a casting sand mold.

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.