A composition which comprises a soluble or partially soluble phosphate, a refractory material and less than 1% of an oxide or hydroxide of magnesium or calcium. The composition may be mixed with water to form an investment casting slurry into which a wax pattern may be dipped. Slurry coated onto the pattern may be set by applying a stucco composition which comprises an oxide or hydroxide of magnesium or calcium. Coats of set slurry may be built up on the pattern to form an investment casting shell.

A composition which comprises a soluble or partially soluble phosphate, a refractory material and less than 1% of an oxide or hydroxide of magnesium or calcium. The composition may be mixed with water to form an investment casting slurry into which a wax pattern may be dipped. Slurry coated onto the pattern may be set by applying a stucco composition which comprises an oxide or hydroxide of magnesium or calcium. Coats of set slurry may be built up on the pattern to form an investment casting shell.

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.

A molding material mixture contains cellulose nanofibers (CNFs) and at least one base material selected from the group consisting of a resin and fibers. A hydrophobic polymer is chemically bonded to at least some of the OH groups of the cellulose nanofibers. The base material and the cellulose nanofibers are ground or pelletized. A method for producing the molding material mixture includes the following: a pre-irradiation step of applying an aqueous dispersion of CNFs to a base material sheet or immersing a base material sheet in the CNF aqueous dispersion, irradiating the base material sheet with an electron beam, and bringing the base material sheet into contact with an aqueous solution or an aqueous dispersion containing a hydrophobic monomer so that the hydrophobic monomer is graft-polymerized onto the CNFs, or a simultaneous irradiation step of mixing an aqueous dispersion of CNFs with a hydrophobic monomer to form a solution, applying the mixed solution to a base material sheet or immersing a base material sheet in the mixed solution, and irradiating the base material sheet with an electron beam so that the hydrophobic monomer is graft-polymerized onto the CNFs; a drying step; and a grinding or pelletizing step. The present invention provides a molding material mixture that contains cellulose nanofibers and at least one base material selected from the group consisting of a resin and fibers, and that can be handled as a ground product or pellets, and also provides a method for producing the molding material mixture.

A molding material mixture contains cellulose nanofibers (CNFs) and at least one base material selected from the group consisting of a resin and fibers. A hydrophobic polymer is chemically bonded to at least some of the OH groups of the cellulose nanofibers. The base material and the cellulose nanofibers are ground or pelletized. A method for producing the molding material mixture includes the following: a pre-irradiation step of applying an aqueous dispersion of CNFs to a base material sheet or immersing a base material sheet in the CNF aqueous dispersion, irradiating the base material sheet with an electron beam, and bringing the base material sheet into contact with an aqueous solution or an aqueous dispersion containing a hydrophobic monomer so that the hydrophobic monomer is graft-polymerized onto the CNFs, or a simultaneous irradiation step of mixing an aqueous dispersion of CNFs with a hydrophobic monomer to form a solution, applying the mixed solution to a base material sheet or immersing a base material sheet in the mixed solution, and irradiating the base material sheet with an electron beam so that the hydrophobic monomer is graft-polymerized onto the CNFs; a drying step; and a grinding or pelletizing step. The present invention provides a molding material mixture that contains cellulose nanofibers and at least one base material selected from the group consisting of a resin and fibers, and that can be handled as a ground product or pellets, and also provides a method for producing the molding material mixture.

A method of producing an investment casting ceramic core is provided that includes: providing a core body consisting of a leachable material; surrounding the core body with a mold composition within a vessel, which mold composition is configured to solidify; leaching the core body from the mold composition subsequent to the mold composition solidifying, thereby leaving an internal cavity within the solidified mold composition; depositing a ceramic composition within the internal cavity of the solidified mold composition; sintering the ceramic composition to a solid ceramic core; and removing the solid ceramic core from the mold composition.

A method of producing an investment casting ceramic core is provided that includes: providing a core body consisting of a leachable material; surrounding the core body with a mold composition within a vessel, which mold composition is configured to solidify; leaching the core body from the mold composition subsequent to the mold composition solidifying, thereby leaving an internal cavity within the solidified mold composition; depositing a ceramic composition within the internal cavity of the solidified mold composition; sintering the ceramic composition to a solid ceramic core; and removing the solid ceramic core from the mold composition.

Molding material mixes that contain a polyurethane binder based on phenolic resins of the benzyl ether type and polyisocyanates are characterized by the inclusion of a polybutadiene derivative. In one case, the polybutadiene derivative has epoxide groups and hydroxyl groups. In another case, the polybutadiene derivative has succinic acid anhydride groups. Molds, cores and risers are produced using these molding material mixes. Inclusion of the polybutadiene derivatives results in a reduction of sand adhesions in the molding process.

A composition which comprises a soluble or partially soluble phosphate, a refractory material and less than 1% of an oxide or hydroxide of magnesium or calcium. The composition may be mixed with water to form an investment casting slurry into which a wax pattern may be dipped. Slurry coated onto the pattern may be set by applying a stucco composition which comprises an oxide or hydroxide of magnesium or calcium. Coats of set slurry may be built up on the pattern to form an investment casting shell.

A composition which comprises a soluble or partially soluble phosphate, a refractory material and less than 1% of an oxide or hydroxide of magnesium or calcium. The composition may be mixed with water to form an investment casting slurry into which a wax pattern may be dipped. Slurry coated onto the pattern may be set by applying a stucco composition which comprises an oxide or hydroxide of magnesium or calcium. Coats of set slurry may be built up on the pattern to form an investment casting shell.