Method for post-treating and a post-treatment system

Patent metadata

Field	Value
Publication number	US-11738528-B2
Application number	US-201716475594-A
Country	US
Kind code	B2
Filing date	Dec 8, 2017
Priority date	Jan 18, 2017
Publication date	Aug 29, 2023
Grant date	Aug 29, 2023

Abstract

A method for post-treating a three-dimensional object produced by selectively solidifying, layer by layer, of a building material in powder form and/or post-treating unsolidified building material in which the three-dimensional object is embedded. The three-dimensional object and/or the unsolidified building material may be treated with a liquid. The liquid may comprises a liquid carrier substance and at least one further substance that reduces surface tension of the carrier substance.

First claim

The invention claimed is:

1. A method for post-treating unsolidified building material, comprising:
producing a three-dimensional object by selectively solidifying, layer by layer, a building material in powder form such that the three-dimensional object is embedded in the unsolidified building material;
treating the unsolidified building material with a liquid; and
drying the unsolidified building material after the unsolidified building material has been treated with the liquid,
wherein the liquid comprises a liquid carrier substance and at least one further substance that reduces surface tension of the carrier substance; and
wherein the carrier substance and the at least one further substance are matched to one another such that, after drying the unsolidified building material, no residues remain on the unsolidified building material, which residues lead to an incompatible material combination and/or contamination with regard to further use.

2. The method according to claim 1 , wherein the at least one further substance is more volatile than the carrier substance.

3. The method according to claim 1 , wherein the at least one further substance is an alcohol.

4. The method according to claim 1 , wherein:
a concentration of the at least one further substance in the liquid is at least 0.1 percent by weight; and/or
the concentration of the at least one further substance in the liquid is at most 45 percent by weight.

5. The method according to claim 1 , wherein:
the liquid carrier substance includes water; and
a concentration of the water in the liquid is at least 65 percent by weight and/or the concentration of the water in the liquid is 99.5 percent by weight at most.

6. The method according to claim 1 , wherein the building material in powder form comprises at least one of:
a polymer comprising at least one of polyetherimides, polycarbonates, polyphenylene sulfones, polyphenylene oxides, polyethersulfones, acrylonitrile-butadiene-styrene copolymers, polyacrylates, polyesters, polyamides, polyaryletherketones, polyethers, polyurethanes, polyimides, polyamide-imides, or polyolefins;
a copolymer comprising at least two different monomer units of the polymers; or
a polyblend based on at least two of the copolymers and/or polymers.

7. The method according to claim 6 , wherein the at least one further substance is a substance used for preparing the building material in powder form.

8. The method according to claim 6 , wherein the building material in powder form comprises a polyamide.

9. The method according to claim 8 , wherein the building material in powder form comprises a PA12.

10. The method according to claim 1 , wherein the step of treating with the liquid is carried out by at least partially immersing:
the unsolidified building material in the liquid; or
the three-dimensional object and the unsolidified building material in the liquid.

11. The method according to claim 10 , wherein:
a force is exerted on the unsolidified building material or both the three-dimensional object and the unsolidified building material; and
the force is opposed to the buoyancy force acting on one or both of the three-dimensional object or the unsolidified building material.

12. The method according to claim 1 , wherein the unsolidified building material is located in channels and/or cavities of the three-dimensional object, and the method further comprises:
detaching the unsolidified building material from the channels and/or the cavities of the three-dimensional object;
treating one or both of the unsolidified building material located in the channels and/or the cavities of the three-dimensional object or the three-dimensional object with one or more of ultrasound, infrasound, and a jet of the liquid; and/or
agitating the liquid by one or more of shaking, stirring, or swiveling.

13. The method according to claim 1 , wherein the step of drying comprises:
drying at least a part of the unsolidified building material by one or more of a centrifuge, a gas flow, or a heating; or
drying the three-dimensional object and at least a part of the unsolidified building material by one or more of the centrifuge, the gas flow, or the heating.

14. The method according to claim 1 , wherein:
the post-treatment is implemented by at least two post-treatment steps carried out one after the other; and
at least one post-treatment step is implemented by a further liquid.

15. The method according to claim 1 , wherein:
the post-treatment is implemented by at least two post-treatment steps carried out one after the other; and
at least one post-treatment step comprises waiting for a predetermined resting term.

16. The method according to claim 1 , wherein the liquid is cleared from unsolidified building material by sedimentation and/or filtration.

17. The method according to claim 1 , further comprising post-treating the three-dimensional object.

18. The method according to claim 17 , wherein the three-dimensional object is treated with the liquid.

19. A method for post-treating unsolidified building material, comprising:
producing a first three-dimensional object by selectively solidifying, layer by layer, a building material in powder form such that the first three-dimensional object is embedded in the unsolidified building material;
selecting a liquid that includes a liquid carrier substance and at least one further substance that reduces a surface tension of the carrier substance, the selecting being performed so as to reduce a surface tension of the liquid on the unsolidified building material when the unsolidified building material is cooled with the liquid;
cooling the unsolidified building material with the liquid;
drying the unsolidified building material after the unsolidified building material has been cooled with the liquid so as to produce a treated unsolidified building material; and
producing a second three-dimensional object by selectively solidifying, layer by layer, the treated unsolidified building material.

Assignees

• Eos Gmbh Electro Optical Systems

Inventors

• Pfefferkorn Florian

Classifications

• B29C71/0009 Primary

  using liquids, e.g. solvents, swelling agents (spectacle cases, e.g. for cleaning contact lenses A45C11/04; disinfecting or sterilising contact lenses A61L12/00, using liquid substances A61L2/20; cleaning involving the use of liquid in general B08B3/00; for hydrating contact lenses B29D11/00067) · CPC title

• B22F10/28

  Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM] · CPC title

• B22F10/68

  Cleaning or washing · CPC title

• B29C35/16

  Cooling {(cooling extruded material B29C48/911; cooling preforms for blow moulding B29C49/6427; cooling blown articles B29C49/66; cooling tyres during post cure inflation B29D30/0643)} · CPC title

• B29C64/153

  using layers of powder being selectively joined, e.g. by selective laser sintering or melting · CPC title