Material system for producing a molded part using a water-soluble casting mold

Patent metadata

Field	Value
Publication number	US-11072090-B2
Application number	US-201815943874-A
Country	US
Kind code	B2
Filing date	Apr 3, 2018
Priority date	Feb 28, 2013
Publication date	Jul 27, 2021
Grant date	Jul 27, 2021

Abstract

A material system for producing a water-soluble casting mold, comprising at least one water-soluble material for building a casting mold in a layering method, as well as comprising at least one material for sealing the surface of the casting mold. The water-soluble material is a material for building the casting mold using a powder bed-based layering method. The sealing material is preferably water insoluble. The material system may also include a free-flowing, hardenable material, which is preferably a hydraulically setting material. The materials of the casting mold are preferably dissolved with the aid of an aqueous solution, and in particular with the aid of a heated aqueous solution.

First claim

What is claimed is:

1. A casting mold or core comprising:
a) a water-soluble printed part having an open pore network and a porous surface formed by a layering method from at least one particulate material and at least one water-soluble binder; and
b) at least one sealing material sealing the porous surface of the printed part and smoothing out roughness of the surface;

wherein the sealing material is a water-insoluble material; and the water-soluble binder includes at least one inorganic compound.

2. The casting mold or core of claim 1 , wherein the casting mold dissolves in water in an autoclave at 80° C., upon which the sealing material is capable of being removed from a molded part without residue.

3. The casting mold or core of claim 1 , wherein pores of the casting mold due to the particulate material are penetrated by the sealing material.

4. The casting mold or core of claim 1 , wherein the at least one inorganic compound includes a sodium silicate, or a potassium silicate.

5. The casting mold or core of claim 4 , wherein the casting mold is dissolved in an autoclave at about 80° C., wherein the sealing material can then be removed from a molded part without residue.

6. The casting mold or core of claim 5 , wherein a hardening material is included for molding a part, wherein the hardening material is a material that transitions from a free-flowing state to a hardened state by means of a chemical reaction.

7. The casting mold or core of claim 6 , wherein the hardening material is a hydraulically setting material that hardens due to the formation of a crystalline structure.

8. The casting mold or core of claim 6 , wherein the hardening material hardens by a polymerization reaction.

9. The casting mold or core of claim 1 , wherein the at least one inorganic compound includes a sheet silicate.

10. The casting mold or core of claim 1 , wherein the sealing material includes a wax, a fatty acid, a water-insoluble polymer, a stearyl alcohol, a cetyl alcohol, or a mixture thereof.

11. The casting mold or core of claim 10 , wherein the water soluble binder has a solubility in water of greater than 1 g/liter at ambient conditions, and the material for sealing has a solubility in water of less than 1 g/liter.

12. The casting mold or core of claim 11 , wherein the material for sealing is liquified upon heating above its melting temperature.

13. The casting mold or core of claim 11 , wherein the sealing material is dissolved in a volatile, organic solvent for applying to a surface of the casting mold.

14. The casting mold or core of claim 1 , wherein the sealing material closes pores of the casting mold caused by the particulate material.

15. A water-soluble casting mold or core produced from a molding system comprising:
a) a build material comprising at least one water-soluble material for building a casting mold or core having an open pore network with a porous surface in a layering method, wherein the build material includes at least one particulate material for applying in layers and a separate printing material for applying by an ink-jet print head, wherein the printing material or the particulate material includes a water-soluble binder; and
b) at least one material for sealing the porous surface of the casting mold or core;

wherein the water-soluble binder includes at least one polysaccharide, at least one salt, or at least one water-soluble polymer;
wherein the material for sealing includes a wax, a fatty acid, a water-insoluble polymer, a stearyl alcohol, a cetyl alcohol, or a mixture thereof;
wherein the casting mold or core has an open pore network and a porous surface and is formed by a layering method from the build material; and
at least one sealing material sealing the porous and smoothing out roughness of the surface;
wherein the sealing material is a water-insoluble material.

16. A water-soluble casting mold or core produced from a material system comprising:
a) a build material comprising at least one water-soluble material for building a casting mold or core having an open pore network with a porous surface in a layering method, wherein the build material includes at least one particulate material for applying in layers and a separate printing material for applying by an ink-jet print head, wherein the printing material or the at least one particulate material includes at least one water-soluble binders; and
b) at least one material for sealing the porous surface of the casting mold or core;

wherein the at least one water-soluble binder includes at least one inorganic compound
wherein the casting mold or core has an open pore network and a porous surface and is formed by a layering method from the build material; and
at least one sealing material sealing the porous surface and smoothing out roughness of the surface;
wherein the sealing material is a water-insoluble material.

Assignees

• Voxeljet Ag
• FluidSolids AG

Inventors

• Günther Daniel
• Gnüchtel Ingo
• Karrer Beat

Classifications

• B29C64/165

  using a combination of solid and fluid materials, e.g. a powder selectively bound by a liquid binder, catalyst, inhibitor or energy absorber · CPC title

• B28B7/342 Primary

  which are at least partially destroyed, e.g. broken, molten, before demoulding; Moulding surfaces or spaces shaped by, or in, the ground, or sand or soil, whether bound or not; Cores consisting at least mainly of sand or soil, whether bound or not · CPC title

• B29C33/52

  soluble or fusible {(in particular used in injection moulding B29C45/4457)} · CPC title

• B29C33/3842

  Manufacturing moulds, e.g. shaping the mould surface by machining · CPC title

• B28B7/346

  Manufacture of moulds · CPC title