SUPPORT MATERIAL FOR DIGITAL MANUFACTURING SYSTEMS

• US 20100096072A1
• Filed: 07/24/2009
• Published: 04/22/2010
• Est. Priority Date: 10/17/2008
• Status: Active Grant

• Current Assignee: Stratasys Incorporated
• Original Assignee: Stratasys Incorporated
• Inventors: Bye, Jeffrey F., Hopkins, Paul E., Priedeman, William R. JR.
• Granted Patent: US 8,246,888 B2
• Time in Patent Office: Days
• US Class Current: 156/155
• CPC Class Codes: B29C 64/40 Structures for supporting 3D objects during manufacture and intended to be sacrificed after completion thereof
• 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: C08L 25/08 Copolymers of styrene C08L29/08, C08L35/06, C08L55/02 take precedence
• CPC Class Codes: C08L 2666/04 Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: C08L 33/02 Homopolymers or copolymers of acids; Metal or ammonium salts thereof
• CPC Class Codes: C08L 33/068 containing glycidyl groups

Abstract

A support material feedstock comprising a first copolymer and a polymeric impact modifier, where the first copolymer includes a first monomer unit comprising a carboxyl group and a second monomer unit comprising a phenyl group.

Claims

1. A support material feedstock for use with a digital manufacturing system, the support material feedstock comprising:

a first copolymer comprising;

a first monomer unit comprising a carboxyl group; and

a second monomer unit comprising a phenyl group; and

a polymeric impact modifier.

2. The support material feedstock of claim 1, wherein the first monomer unit is polymerized from methacrylic acid, and wherein the second monomer unit is polymerized from styrene.

3. The support material feedstock of claim 1, wherein the first copolymer further comprises a third monomer unit comprising a carboxylate ester group.

4. The support material feedstock of claim 3, wherein the third monomer unit is polymerized from an alkyl acrylate.

5. The support material feedstock of claim 1, wherein the polymeric impact modifier comprises a second copolymer that includes an epoxy-terminated carboxylate ester group.

6. The support material feedstock of claim 5, wherein the second copolymer is polymerized from monomers comprising ethylene and glycidyl methacrylate.

7. The support material feedstock of claim 5, wherein the second copolymer further includes a carboxylate ester group.

8. The support material feedstock of claim 1, wherein the support material feedstock is soluble in an alkaline aqueous solution.

9. A support material feedstock for use with a digital manufacturing system, the support material feedstock comprising:

a first copolymer comprising;

a plurality of first monomer units comprising carboxyl groups;

a plurality of second monomer units comprising phenyl groups; and

a plurality of third monomer unit comprising carboxylate ester groups; and

a second copolymer comprising a plurality of epoxy-terminated carboxylate ester groups.

10. The support material feedstock of claim 9, wherein the first monomer units constitute from about 10% by weight to about 50% by weight of the first copolymer, wherein the second monomer units constitute from about 30% by weight to about 60% by weight of the first copolymer, and wherein the third monomer units constitute from about 5% by weight to about 40% by weight of the first copolymer.

11. The support material feedstock of claim 10, wherein the first monomer units constitute from about 30% by weight to about 45% by weight of the first copolymer, wherein the second monomer units constitute from about 35% by weight to about 50% by weight of the first copolymer, and wherein the third monomer units constitute from about 15% by weight to about 25% by weight of the first copolymer.

12. The support material feedstock of claim 9, wherein the second copolymer further comprises a plurality of carboxylate ester groups.

13. The support material feedstock of claim 9, wherein the second copolymer constitutes about 1% by weight to about 25% by weight of the support material feedstock.

14. The support material feedstock of claim 9, and further comprising a third copolymer polymerized from monomers of methacrylic acid.

15. A method for building a three-dimensional model with a digital manufacturing system, the method comprising:

depositing a support material into a build chamber of the digital manufacturing system using a layer-based additive technique to form a support structure, wherein the support material comprises a first copolymer and a polymeric impact modifier, the first copolymer comprising a plurality of first monomer units comprising carboxyl groups and a plurality of second monomer units comprising phenyl groups;

depositing a modeling material into the build chamber of the digital manufacturing system using the layer-based additive technique to form the three-dimensional model, wherein the three-dimensional model comprises at least one overhanging region supported by the support structure; and

substantially removing the support structure from the three-dimensional model with an aqueous solution.

16. The method of claim 15, wherein substantially removing the support structure from the three-dimensional model with the aqueous solution comprises immersing the support structure and the three-dimensional model into a bath of the aqueous solution.

17. The method of claim 15, wherein the aqueous solution comprises an alkaline aqueous solution.

18. The method of claim 15, and further comprising maintaining the build chamber at one or more temperatures ranging from about 85°

C. to about 110°

C.

19. The method of claim 15, wherein the first copolymer further comprises a plurality of third monomer units comprising carboxylate ester groups.

20. The method of claim 15, wherein the polymeric impact modifier comprises a second copolymer having a plurality of epoxy-terminated carboxylate ester groups.