Binder composition for additive manufacturing

Patent metadata

Field	Value
Publication number	US-2021053113-A1
Application number	US-202016998527-A
Country	US
Kind code	A1
Filing date	Aug 20, 2020
Priority date	Aug 23, 2019
Publication date	Feb 25, 2021
Grant date	—

Abstract

Methods of additive manufacturing, binder compositions for additive manufacturing, and articles produced by and/or associated with methods of additive manufacturing are generally described.

First claim

What is claimed is:

1 . A method of additive manufacturing a metal-based composite structure by binder jet printing, the method comprising:
depositing a first layer of metal powder; depositing a binder composition on at least a portion of the first layer of metal powder, the binder composition comprising water and a low molecular weight polymer including an acrylic acid repeat unit, wherein the binder composition has a pH of greater than or equal to 4; and drying and/or cross-linking at least the binder composition deposited on the first layer of the metal powder, thereby forming a metal-based composite structure.

2 . (canceled)

3 . The method of claim 1 , wherein the low molecular weight polymer has a weight average molecular weight of less than or equal to 40 kDa.

4 - 10 . (canceled)

11 . The method of claim 1 , wherein the binder composition further comprises an adhesion promoter.

12 . The method of claim 11 wherein the adhesion promoter comprises a functional group capable of binding to the metal powder.

13 . The method of claim 12 , wherein the functional group capable of binding to the metal powder is a sulfur-containing functional group.

14 . The method of claim 13 , wherein the sulfur-containing functional group comprises a thiol.

15 . The method of claim 12 , wherein the functional group capable of binding to the metal powder is a first functional group, and the adhesion promoter further comprises a second functional group.

16 . The method of claim 15 , wherein the second functional group is a nucleophilic functional group or an electrophilic group.

17 . The method of claim 15 , wherein the adhesion promoter further comprises a third functional group.

18 . The method of claim 17 , wherein the third functional group is a nucleophilic group or an electrophilic group.

19 . The method of claim 11 , wherein the adhesion promoter is or comprises cysteine, cystine, methionine, homocysteine, an amine thiol, dithiothreitol, mercaptoethanol, a thiocarboxylic acid, and/or a thiocarboxylate.

20 - 26 . (canceled)

27 . The method of claim 1 , wherein the metal powder comprises gold metal and/or a gold alloy.

28 - 71 . (canceled)

72 . A binder composition for additive manufacturing of metal objects by binder jetting, the binder composition comprising:
water; a low molecular weight polymer including an acrylic acid repeat unit; a cross-linking agent comprising a polyol, a multifunctional amine, and/or a multifunctional thiol; and a pH modifier.

73 - 77 . (canceled)

78 . The binder composition of claim 72 , wherein the binder composition further comprises an adhesion promoter.

79 . The binder composition of claim 78 , wherein the adhesion promoter comprises a functional group capable of binding to a metal powder.

80 . The binder composition of claim 79 , wherein the functional group capable of binding to a metal powder is a sulfur-containing functional group.

81 - 116 . (canceled)

117 . A metal-based composite structure formed by additive manufacturing, the metal-based composite structure comprising:
a metal powder, wherein the wt % of the metal powder in the metal-based composite structure is between 92 wt % and 99.9 wt %; and a binder, wherein the binder comprises a low molecular weight polymer including an acrylic acid repeat unit.

118 - 130 . (canceled)

131 . The metal-based composite structure formed by additive manufacturing of claim 117 , wherein the binder composition further comprises an adhesion promoter.

132 . The metal-based composite structure formed by additive manufacturing of claim 131 , wherein the adhesion promoter comprises a functional group capable of binding to the metal powder.

133 . The metal-based composite structure formed by additive manufacturing of claim 132 , wherein the functional group capable of binding to the metal powder is a sulfur-containing functional group.

134 - 141 . (canceled)

Assignees

• Desktop Metal Inc

Inventors

• Renner Christopher Benjamin
• Rushkin Ilya L
• Nick Robert J
• Sachs Emanuel M

Classifications

• B22F1/103

  containing an organic binding agent comprising a mixture of, or obtained by reaction of, two or more components other than a solvent or a lubricating agent · CPC title

• B22F1/10

  Metallic powder containing lubricating or binding agents; Metallic powder containing organic material · CPC title

• B33Y10/00 Primary

  Processes of additive manufacturing · CPC title

• C08L33/02 Primary

  Homopolymers or copolymers of acids; Metal or ammonium salts thereof · CPC title

• Y02P10/25

  Process efficiency · CPC title