Support materials for 3D printing

• US 10,201,933 B2
• Filed: 06/02/2016
• Issued: 02/12/2019
• Est. Priority Date: 06/09/2015
• Status: Active Grant

• Current Assignee: Dow Global Technologies LLC (Dow, Inc.)
• Original Assignee: Dow Global Technologies LLC (Dow, Inc.)
• Inventors: Bayer, Roland, Wagner, Anette, Pyzik, Aleksander J., Allen, Sharon
• Primary Examiner(s): Ahmed, Sheeba
• Application Number:
  US15/580,206
• Publication Number:
  US 20180147785A1
• Time in Patent Office: 985 Days
• Field of Search: None
• CPC Class Codes: B29C 64/40 Structures for supporting 3D objects during manufacture and intended to be sacrificed after completion thereof
• CPC Class Codes: B29K 2001/08 Cellulose derivatives
• CPC Class Codes: B29K 2101/12 Thermoplastic materials
• CPC Class Codes: B29K 2995/0062 water-soluble
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 70/00 Materials specially adapted for additive manufacturing
• CPC Class Codes: B33Y 70/10 Composites of different types of material, e.g. mixtures of ceramics and polymers or mixtures of metals and biomaterials
• CPC Class Codes: C08L 1/284 with hydroxylated hydrocarbon radicals
• CPC Class Codes: C09D 101/284 with hydroxylated hydrocarbon radicals

Abstract

A three-dimensionally printed article is comprised of a hydroxyethyl methylcellulose (HEMC) having a DS of 1.7 to 2.5 and an MS of at least 0.5, wherein DS is the degree of substitution of methoxyl groups and MS is the molar substitution of hydroxyethoxyl groups. The HEMC may advantageously be used as a support material when making a three-dimensionally printed article using a build material such as a different thermoplastic polymer such as a poly(acrylonitrile-butadiene-styrene), polylactic acid, polyethylene and polyprophylene. When the HEMC is a support material it may be easily removed from the build material by contacting the three dimensionally printed article with water, which may be at ambient temperatures and a pH that is neutral or close to neutral.

Claims

1. A three-dimensionally printed article comprising a hydroxyethyl methylcellulose having a DS of 1.7 to 2.5 and an MS of at least 0.5, wherein DS is the degree of substitution of methoxyl groups and MS is the molar substitution of hydroxyethoxyl groups, wherein the article is comprised of a plurality of layers of the hydroxyethyl methyl cellulose.

2. The article of claim 1 wherein the three-dimensionally printed article is comprised of a build material and a support material and the hydroxyethyl methylcellulose is the support material for the build material.

3. The article of claim 1, wherein the hydroxyethyl methylcellulose has a DS of at least 1.8.

4. The article of claim 2 wherein the build material comprises a thermoplastic material.

5. The article of claim 4, wherein the build material is comprised of at least one of a polyolefin, poly(acrylonitrile-butadiene-styrene), polycarbonate, polylactic acid and polyamide.

6. The article of claim 1, wherein the hydroxyethyl methylcellulose has a DS of from 1.8 to 2.5.

7. The article of claim 1, wherein the hydroxyethyl methylcellulose has an MS of from 0.5 to 10.

8. The article of claim 1, wherein the hydroxyethyl methylcellulose is comprised of at least one of a filler, dye, lubricant, surfactant, plasticizer or stabilizer.

9. The article of claim 1, wherein the hydroxyethyl methylcellulose is further comprised of a plasticizer.

10. The article of claim 1, wherein the hydroxyethyl methylcellulose has no plasticizer.

11. The article of claim 1, wherein the hydroxyethyl methylcellulose has a viscosity of 100 mPa×

s or less, the viscosity being measured at a shear rate of 2.55 s−

1 of a 2 weight percent solution of the hydroxyethyl methylcellulose in water at 20°

C.

12. A method of printing a three-dimensional article comprising:

selectively depositing layers of a build material to form the three dimensional article on a substrate; and

supporting at least one of the layers of the build material with a support material, the support material comprising hydroxyethyl methylcellulose having a DS of 1.8 to 2.5 and an MS of at least 0.5 to 2.5, wherein DS is the degree of substitution of methoxyl groups and MS is the molar substitution of hydroxyethoxyl groups.

13. The method of claim 12 wherein at least one of the layers of the build is supported with a support material set forth in any one of claims 2 to 7.

14. The method of claim 12, wherein the layers of the build material are deposited according to an image of the three-dimensional article in a computer readable format.

15. The method of claim 12 further comprising removing the support material from the build material by contacting the support material with water.

16. The method of claim 15, wherein the water has a neutral pH.

17. The method of claim 16, wherein the water is at a temperature of at most about 30°

C.

18. The method of claim 12, wherein the selectively depositing layers are deposited by heating the build material and support material.

19. The method of claim 18, wherein the heating temperature is greater than 100°

C. to 220°

C.