Debindable resins for stereolithographic manufacturing

Patent metadata

Field	Value
Publication number	US-2018133367-A1
Application number	US-201715812801-A
Country	US
Kind code	A1
Filing date	Nov 14, 2017
Priority date	Nov 14, 2016
Publication date	May 17, 2018
Grant date	—

Abstract

Systems, methods, components, and materials are disclosed for stereolithographic fabrication of three-dimensional, dense objects. A resin including a first binder, a second binder, and dispersed particles can be exposed an activation light source to cure at least one of the binders in a layer-by-layer process to form a green object including the first binder, the second binder, and the particles. A dense object, such as a metal object, a ceramic object, or a combination thereof, can be formed from the green object by thermally processing the particles and removing the first binder through a primary debinding process, removing the second binder through a secondary debinding process different from the primary debinding process.

First claim

What is claimed is:

1 . A resin comprising:
a first binder; a second binder different from the first binder and in a mixture with the first binder; and particles suspended in the mixture of the first binder and the second binder, wherein the particles are thermally processable to coalesce with one another into a mass, at least one of the first binder and the second binder is reactive to crosslink or polymerize upon sufficient exposure of the first binder and the second binder to a predetermined wavelength of light, and the first binder and the second binder are separately extractable from the mass following crosslinking or polymerization of the at least one of the first binder and the second binder.

2 . The resin of claim 1 , wherein the particles are sinterable to coalesce with one another into the mass.

3 . The resin of claim 1 , wherein the particles are infiltratable with a liquid metal to coalesce with one another into the mass.

4 . The resin of claim 1 , wherein the first binder is substantially non-reactive under exposure to the predetermined wavelength of light sufficient to cross-link or polymerize the second binder.

5 . The resin of claim 1 , wherein the first binder includes a wax extractable from the second binder by chemical solvation in a non-polar chemical following sufficient exposure of the first binder and the second binder to the predetermined wavelength of light to crosslink or polymerize the second binder.

6 . The resin of claim 1 , wherein the first binder includes a plurality of low-molecular weight constituents, each constituent extractable from the second binder by a chemical solution following sufficient exposure of the first binder and the second binder to the predetermined wavelength of light sufficient to crosslink or polymerize the second binder.

7 . The resin of claim 1 , wherein the particles include metal, ceramic, or combinations thereof.

8 . The resin of claim 1 , wherein the resin is a non-Newtonian fluid at 25° C.

9 . The resin of claim 1 , wherein exposure to light at a wavelength of about 300 nm to about 450 nm is sufficient to crosslink or polymerize at least one of the first binder and the second binder.

10 . The resin of claim 1 , further comprising one or more of a photo-absorber or a photo-initiator suspended in the mixture including the first binder and the second binder.

11 . The resin of claim 1 , wherein a concentration by volume of the particles is within ±25 percent of a tap density of the particles.

12 . The resin of claim 1 , wherein the first binder includes one or more of the following: paraffin wax, carnauba wax, stearic acid, polyethylene glycol, polyoxymethylene, oleic acid, and dibutyl phthalate.

13 . The resin of claim 1 , wherein the second binder includes one or more of the following: poly(methyl methacrylate), polyethylene glycol diacrylate, urethane oligomers functionalized to acrylate groups, epoxy oligomers functionalized to acrylate groups, 1,6-Hexanediol acrylates, or styrene.

14 . A method of additive manufacturing of a three-dimensional object, the method comprising:
providing a layer of a resin on a media source, the resin including particles suspended in a mixture of a first binder and a second binder; directing light energy onto each layer of a plurality of layers of the resin to crosslink or polymerize at least one of the first binder and the second binder of the resin on a substrate carried by a build plate, the light energy directed onto the resin in a respective predetermined pattern associated with each layer to form a three-dimensional object; thermally processing the particles in the three-dimensional object to coalesce the particles to one another; extracting the first binder from the three-dimensional object in a primary debinding process; and extracting the second binder from the three-dimensional object in a secondary debinding process different from the primary debinding process.

15 . The method of claim 14 , wherein thermally processing the particles in the three-dimensional object includes sintering the three-dimensional object.

16 . The method of claim 14 , wherein thermally processing the particles in the three-dimensional object includes infiltrating the three-dimensional object with a liquid metal.

17 . The method of claim 14 , wherein thermally processing the particles in the three-dimensional object includes thermally-activating pyrolysis of at least one of the first binder and the second binder into a ceramic.

18 . The method of claim 14 , wherein one or both of the primary debinding process and the secondary debinding process includes thermal debinding, chemical debinding, or a combination thereof.

19 . The method of claim 14 , wherein directing light energy onto each layer of the plurality of layers of the resin includes crosslinking or polymerizing the first binder and the second binder, and the primary debinding process includes breaking down the crosslinked or polymerized first binder.

20 . The method of claim 19 , wherein the first binder includes acrylic anhydride, methacrylic anhydride, or a combination thereof.

Assignees

• Desktop Metal Inc

Inventors

• Gibson Michael Andrew
• Myerberg Jonah Samuel
• Fulop Ricardo
• Tarkanian Michael J
• Chiang Yet-Ming

Classifications

• B29C64/129

  characterised by the energy source therefor, e.g. by global irradiation combined with a mask · CPC title

• B29C64/124 Primary

  using layers of liquid which are selectively solidified · CPC title

• 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

• A61K6/822

  comprising rare earth metal oxides · CPC title

• A61K6/818

  comprising zirconium oxide · CPC title