Method for producing three-dimensional molded parts and regulating the moisture content in build material

Patent metadata

Field	Value
Publication number	US-2017297263-A1
Application number	US-201515516991-A
Country	US
Kind code	A1
Filing date	Dec 11, 2015
Priority date	Dec 17, 2014
Publication date	Oct 19, 2017
Grant date	—

Abstract

A method for producing three-dimensional molded parts by means of layering, the moisture content of the build material mixture being able to be regulated.

First claim

What is claimed is:

1 . A method for producing three-dimensional molded parts by means of layering comprising the steps of:
a. applying a particulate build material to a build space in a defined layer thickness with the aid of a coater; b. selectively applying a binder fluid to the particulate build material by means of a print head; c. polymerizing the binder fluid with the aid of at least one activators; d. lowering the build space by a distance of the layer thickness, or raising the coater by the distance of one layer thickness; and e. repeating steps a, b, c, and d, until the desired molded part is produced; wherein the particulate build material, the binder fluid and/or the activator includes or is modified with a component for regulating a moisture content of the build material mixture.

2 . A material system for producing three-dimensional models by means of layering, the material system including a particulate build material, a binder fluid, one or multiple activators and/or means with the aid of which the moisture content may be regulated.

3 . The material system of claim 2 , wherein the activator is made of an organic and/or inorganic acid in a proportion of 50% to 90% and/or
the activator includes a humectant.

4 . The material system of claim 2 , wherein the relative proportion of activator with respect to the build material is 0.1% to 1.0%.

5 . The material system of claim 2 , wherein,
the binder fluid is selected from the group of acidically condensable monomers and/or oligomers, and/or the binder fluid includes furfuryl alcohol and/or resol resins, and/or the binder fluid includes cross-linking agents, wetting agents and/or adhesives.

6 . The material system of claim 2 , wherein the build material comprises an inorganic particulate material.

7 . The material system of claim 2 , wherein the particulate material has an average grain size of 50 μm to 1 mm.

8 . A molded body produced according to the method of claim 1 , wherein the molded body is
a casting mold and/or a core in foundry processes or as a mold and/or core for lamination processes, wherein the foundry process is a concrete, mineral or reactive polymer casting process.

9 . The molded body of claim 8 , wherein the molded body is usable as an illustrative model, a sculpture or an element of an add-on part, directly or after an infiltration process.

10 . A device for constructing a molded part by the method according to claim 1 .

11 . The method of claim 1 , wherein the particulate build material includes a sand and the at least one activator is mixed into the particulate build material independently of the point in time of the build process.

12 . The method of claim 11 , wherein the activator includes a humectant.

13 . The material system of claim 2 , wherein
the activator is made of an organic acid or an inorganic acid in a proportion 60% to 80%.

14 . The material system of claim 13 , wherein the acid is a sulfuric acid or p-toluenesulfonic acid.

15 . The material system of claim 3 , wherein the humectant compound including diols.

16 . The material system of claim 11 , wherein the relative proportion of activator with respect to the particulate build material is 0.25% to 0.45%, and the activator includes a humectant.

17 . The material system of claim 16 , wherein the binder fluid is selected from the group of acidically condensable monomers and/or oligomers.

18 . The material system of claim 16 , wherein the binder fluid includes furfuryl alcohol and/or resol resins.

19 . The material system of claim 16 , wherein the binder fluid includes cross-linking agents, wetting agents and/or adhesives.

20 . The material system of claim 16 , wherein the particulate material has an average grain size 100 μm to 500 μm.

Assignees

• Voxeljet Ag

Inventors

• Ederer Ingo
• Günther Daniel
• Günther Johannes
• Gnüchtel Ingo
• Mögele Florian

Classifications

• B33Y80/00

  Products made by additive manufacturing · CPC title

• C09D201/06

  containing oxygen atoms {(C09D201/025 takes precedence)} · CPC title

• B29C33/3807

  Resin-bonded materials, e.g. inorganic particles · CPC title

• B29C64/209

  Heads; Nozzles · CPC title

• C09D7/61

  inorganic · CPC title