3d printing method utilizing heat-curable silicone composition

Patent metadata

Field	Value
Publication number	US-2018186076-A1
Application number	US-201615757113-A
Country	US
Kind code	A1
Filing date	Sep 2, 2016
Priority date	Sep 3, 2015
Publication date	Jul 5, 2018
Grant date	—

Abstract

A method of forming a three-dimensional (3D) article comprises the steps of I) printing a first heat-curable silicone composition with a 3D printer to form a layer, II) heating the layer to form an at least partially cured layer, III) printing a second heat-curable silicone composition on the at least partially cured layer with the 3D printer to form a subsequent layer, and IV) heating the subsequent layer to form an at least partially cured subsequent layer. Optionally, steps III) and IV) can be repeated with independently selected heat-curable silicone composition(s) for any additional layer(s) to form the 3D article. The first and second heat-curable silicone compositions may be the same as or different from one another.

First claim

1 . A method of forming a three-dimensional (3D) article, said method comprising:
I) printing a first heat-curable silicone composition with a 3D printer to form a layer; II) heating the layer to form an at least partially cured layer; III) printing a second heat-curable silicone composition on the at least partially cured layer with the 3D printer to form a subsequent layer; IV) heating the subsequent layer to form an at least partially cured subsequent layer; and, V) optionally, repeating steps III) and IV) with independently selected heat-curable silicone composition(s) for any additional layer(s) to form the 3D article;
wherein the first and second heat-curable silicone compositions are the same as or different from one another, and wherein the first and second heat-curable silicone compositions are not cured via irradiation.

2 . The method according to claim 1 , wherein steps II) and IV) are independently selected from (i) conductive heating via a substrate on which the layer is printed; (ii) heating the particular heat-curable silicone composition via the 3D printer or a component thereof; (iii) infrared heating; (iv) electromagnetic heating; (v) a heating bath with a heat transfer fluid; (vi) heating from an exothermic reaction of the particular heat-curable silicone composition; (vii) magnetic heating; or (viii) any combination of (i) to (vii).

3 . The method according to claim 1 , wherein the first and second heat-curable silicone compositions are the same.

4 . The method according to claim 1 , wherein the first and second heat-curable silicone compositions are independently selected from condensation-curable silicone compositions, hydrosilylation-curable silicone compositions, free radical-curable silicone compositions, ring opening reaction-curable silicone compositions, and dual-cure silicone compositions.

5 . The method according to claim 4 , wherein the first and/or second heat-curable silicone composition(s) comprise(s) a hydrosilylation-curable silicone composition comprising (A) an organopolysiloxane having an average of at least two silicon-bonded alkenyl groups or silicon-bonded hydrogen atoms per molecule; (B) an organosilicon compound having an average of at least two silicon-bonded hydrogen atoms or silicon-bonded alkenyl groups per molecule capable of reacting with the silicon-bonded alkenyl groups or silicon-bonded hydrogen atoms in the organopolysiloxane (A); and (C) a hydrosilylation catalyst.

6 . The method according to claim 4 , wherein the first and/or second heat-curable silicone composition(s) comprise(s) a condensation-curable silicone composition comprising (A′) an organopolysiloxane having an average of at least two silicon-bonded hydroxyl or hydrolysable groups per molecule; optionally (B′) an organosilicon compound having an average of at least two silicon-bonded hydrogen atoms, hydroxyl groups, or hydrolysable groups per molecule; and (C′) a condensation catalyst; and optionally, wherein the condensation-curable silicone composition is a multipart composition, wherein component (A′) is in a first part, component (B′) is in a second part separate from the first part, and component (C′) is in the second part and/or in a third part separate from the first and second parts.

7 . The method according to claim 4 , wherein the first and/or second heat-curable silicone composition(s) comprise(s) a free radical-curable silicone composition comprising (A″) an organopolysiloxane having an average of at least two silicon-bonded unsaturated groups and (C″) an organic peroxide.

8 . The method according to claim 4 , wherein the first and/or second heat-curable silicone composition(s) comprise(s) a ring opening reaction-curable silicone composition comprising (A″′) an organopolysiloxane having an average of at least two epoxy-substituted groups per molecule and (C″′) a curing agent.

9 . The method according to claim 1 , wherein the first and second heat-curable silicone compositions are different from one another.

10 . The method according to claim 1 , wherein the first and/or second heat-curable silicone composition(s) is(are) a multi-part heat-curable silicone composition comprising at least a first part and a second part separate from the first part; and optionally, wherein the separate parts of the multi-part heat-curable silicone composition are mixed in a dual dispense printing nozzle prior to printing.

11 . The method according to claim 1 , wherein the 3D printer is selected from a fused filament fabrication printer, a selective laser sintering printer, a selective laser melting printer, a stereolithography printer, a powder bed (binder jet) printer, a material jet printer, a direct metal laser sintering printer, an electron beam melting printer, a laminated object manufacturing deposition printer, a directed energy deposition printer, a laser powder forming printer, a polyjet printer, an ink-jetting printer, a material jetting printer, and a syringe extrusion printer.

12 . The method according to claim 1 , wherein the at least partially cured layer formed in step II) retains its shape upon exposure to ambient conditions.

13 . The method according to claim 1 , wherein:
a) heat is applied to the first heat-curable silicone composition during step I); b) heating via steps II) and IV) is carried out at a temperature independently selected from above ambient temperature to 300° C.; or c) both a) and b).

14 . The method according to claim 1 , wherein the first and/or second heat-curable composition(s) is(are) shear thinning.

15 . A 3D article formed in accordance with the method of claim 1 .

Assignees

• Dow Corning

Inventors

• Backer Michael W
• Milroy Zachary
• Schaubroeck Sara
• Wolf Hans Peter
• Zhu Bizhong

Classifications

• B29C64/295 Primary

  Heating elements · CPC title

• C08L83/04

  Polysiloxanes · CPC title

• B29C64/118

  using filamentary material being melted, e.g. fused deposition modelling [FDM] · CPC title

• C08G77/08

  characterised by the catalysts used · CPC title

• B29K2083/00

  Use of polymers having silicon, with or without sulfur, nitrogen, oxygen, or carbon only, in the main chain, as moulding material · CPC title