The object of the invention is a method for the layered construction of bodies comprising refractory molding base material and resol resins as binders having, in addition to phenol, ortho- and/or para-substituted phenols as monomer structural elements and three-dimensional bodies produced according to this method, and a binder for 3-dimensionally constructing bodies, in particular molds and cores for the metal casting.

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 is casting sand including sand and a solid acid catalyst mixed with the sand.

Provided is casting sand including sand and a solid acid catalyst mixed with the sand.

A ceramic casting shell is formed by a method comprising the steps of coating a wax former with one or more layers of a ceramic slurry; drying the or each layer of ceramic slurry; wherein the dried layer or layers of ceramic slurry form a ceramic shell; applying over the ceramic shell, a coating of a polymer material; heating the formed assembly to melt and remove the wax former, wherein the polymer coating acts as a strengthening layer to the ceramic shell during the wax removal process; and subsequent to removal of the wax former, heating the ceramic shell to melt and remove the polymer coating. The polymer coating is preferably the outer coating of the ceramic shell. The polymer coating may be applied by spraying, dipping or painting onto the ceramic shell.

A method for producing a sand mold includes mixing artificial sand with a furan resin composition including a furan resin precursor, preparing molding sand having the artificial sand and a surface-modified layer containing a resin cured product covering the artificial sand and including a curing agent attached to the surface-modified layer by mixing the curing agent including xylene sulfonic acid with the artificial sand with which the furan resin composition is mixed, and curing the furan resin composition, after mixing the artificial sand with the furan resin composition, and curing an added portion of the binder in the molding sand by adding the binder to the molding sand. In the step of curing the added portion of the binder, the curing agent for curing the furan resin composition is used also as a curing agent for curing the binder.

A no bake process is provided for preparing a foundry shape. A major amount of an appropriate foundry aggregate, especially a sand that has been mechanically-reclaimed, is mixed with an amount of halloysite tubes. A binder system, especially a water-based binder, such as an aqueous alkaline phenolic resole resin, is added to the mixed aggregate and halloysite, and a liquid co-reactant for curing the binder is also added. By intimately mixing the components, a foundry molding compound is formed and it can be placed into a mold or patter to cure into a foundry shape. When removed from the mold or pattern, the foundry shape can be used to cast molten metal.

The invention relates to a binder based on phenolic resins of the benzyl ether type and isocyanate compounds having at least two isocyanate groups, containing free phenol and free hydroxybenzyl alcohols in the polyol component. The invention further relates to mold material mixtures containing the binder and to cores, molds, or risers produced with the mold material mixtures and to the use thereof in metal casting.

A no bake process is provided for preparing a foundry shape. A major amount of an appropriate foundry aggregate, especially a sand that has been mechanically-reclaimed, is mixed with an amount of halloysite tubes. A binder system, especially a water-based binder, such as an aqueous alkaline phenolic resole resin, is added to the mixed aggregate and halloysite, and a liquid co-reactant for curing the binder is also added. By intimately mixing the components, a foundry molding compound is formed and it can be placed into a mold or patter to cure into a foundry shape. When removed from the mold or pattern, the foundry shape can be used to cast molten metal.

Curable compositions contain at least one polymerizable ionic species and, when cured (for example, by photocuring), provide cured compositions which are thermoplastic and yet fragmentable by a protic liquid medium such as water. The polymerizable ionic species corresponds to Formula (I) A+B− wherein A+ is a cationic species having a cationic functional group and a first polymerizable, ethylenically unsaturated functional group; and B″ is an anionic species having an anionic functional group and a second polymerizable, ethylenically unsaturated functional group which is the same as or different from the first polymerizable, ethylenically unsaturated functional group. The curable compositions are useful for forming sacrificial or temporary articles, for example by three-dimensional printing methods.