Methods and systems of three dimensional printing

1. A three-dimensional printing system, comprising:

a support bath including a support material comprising a nanoclay prepared as a yield stress suspension, wherein the support material has a gel-like state when a stress applied to the support material is less than a yield stress, wherein the support material has a free-flow state when the stress applied to the support material is above the yield stress, wherein when the stress applied to the support material changes from above the yield stress to below the yield stress, the support material returns to the gel-like state; and

a printing device for delivering a plurality of discrete volumes of a liquid to the support bath, wherein each discrete volume of liquid is delivered to a specified voxel, where each specified voxel corresponding to a discrete volume of liquid is in a different location, wherein as each discrete volume of liquid is delivered in the support bath, the support material supports the discrete volume of liquid, wherein the plurality of discrete volumes of liquid build material form a liquid three dimensional structure,

wherein prior to delivering the plurality of discrete volumes of the liquid build material to each specified voxel, the support material in each specified voxel is in the gel-like state, wherein as the printing devices moves to each specified voxel the printing produces stress applied to the support material in that specified voxel that is above the yield stress so that upon printing each discrete volume of the liquid build material in each specified voxel the support material in each specified voxel converts into the free-flow state, wherein the support material flows out of each specified voxel as the discrete volume of the liquid build material is printed to each specified voxel, wherein after each discrete volume of the liquid build material is printed to each specified voxel, the support material in the free-flow state transforms back to the gel-like state to support the discrete volume of the liquid build material once the stress applied to the support material is below the yield stress.

2. The system of claim 1 , wherein the support material comprises a smectite material.

3. The system of claim 2 , wherein the smectite material is selected from the group consisting of: montmorillonite (MMT), nontronite, Saponite, hectorite, and a combination thereof.

4. The system of claim 1 , wherein the support material comprises Laponite EP®, Laponite RD®, Laponite XLG®, Laponite XL21®, Laponite D®, or a combination thereof.

5. The system of claim 1 , wherein the support bath is at least one of: ion insensitive, UV transparent, and thermally stable.

6. The system of claim 1 , wherein the support material further comprises an aqueous solution, wherein preparing the yield stress suspension comprises dispersing the nanoclay in the aqueous solution and continuously mixing for a mixing time.

7. The system of claim 6 , wherein the aqueous solution comprises a dionized water.

8. The system of claim 1 , wherein a concentration of the nanoclay in the yield stress suspension ranges from about 0.5% w/v to about 8.0% w/v.

9. The system of claim 1 , wherein the support material has a pH value of about 7.0 or higher.

10. The system of claim 1 , wherein the liquid comprises a dispensable build material.

11. The system of claim 1 , wherein the liquid comprises a natural polymer or synthetic polymer.

12. The system of claim 11 , wherein the natural polymer is selected from a group consisting of: alginate, gelatin, chitosan, collagen, Matrigel, agarose, and fibrin.

13. The system of claim 11 , wherein the synthetic polymer is selected from a group consisting of: ethylene glycol, polyethylene glycol, polyvinyl alcohol, Pluronic, SU-8, and polydimethylsiloxane.

14. A method to form a three-dimensional structure, comprising:

a) providing a support bath including a support material comprising a nanoclay prepared as a yield stress suspension, wherein the support material has a gel-like state when a stress applied to the support material is less than a yield stress, wherein the support material has a free-flow state when the stress applied to the support material is above the yield stress, wherein as the stress applied to the support material changes from above the yield stress to below the yield stress, the support material returns to the gel-like state;

b) printing a first liquid in a first voxel, wherein prior to printing the first liquid in the first voxel, the support material in the first voxel is in the gel-like state, wherein the printing produces stress applied to the support material that is above the yield stress so that upon printing the first liquid in the first voxel the support material in the first voxel converts into the free-flow state, wherein the support material flows out of the first voxel as the first liquid is printed, wherein the support material in the free-flow state transforms back to the gel-like state to support the first liquid in the first voxel when the stress applied is below the yield stress;

c) repeating step b) for a plurality of voxels, wherein the liquid in the plurality of voxels is part of a liquid three-dimensional structure; and

d) causing a phase change in the liquid three-dimensional structure to form the three dimensional structure, which can be removed from the support material.

15. The method of claim 14 , wherein the support material comprises a smectite material.

16. The method of claim 15 , wherein the smectite material is selected from the group consisting of: montmorillonite (MMT), nontronite, Saponite, hectorite, and a combination thereof.

17. The method of claim 14 , wherein the support material comprises Laponite EP®, Laponite RD®, Laponite XLG®, Laponite XL21®, Laponite D®, or a combination thereof.