3d lattice supports for additive manufacturing

Patent metadata

Field	Value
Publication number	US-2018304541-A1
Application number	US-201815938848-A
Country	US
Kind code	A1
Filing date	Mar 28, 2018
Priority date	Apr 19, 2017
Publication date	Oct 25, 2018
Grant date	—

Abstract

A composite article useful in additive manufacturing typically includes: (a) optionally, but preferably, a base; (b) at least one three-dimensional lattice support connected to the base (when present); (c) at least one three-dimensional object, the object having a bottom surface portion, a top surface portion, at least one upright segment, and optionally at least one overhanging segment (e.g., a bridging segment; a cantilevered segment, etc.); (d) interconnecting supports connecting (i) each the at least one overhanging segment to the three-dimensional lattice and/or (ii) each at least one upright segment to the three-dimensional lattice; and (e) optionally, but in some embodiments preferably, a plurality of elongate stand-off supports interconnecting the bottom surface portion of each the three-dimensional object to the base.

First claim

1 . A composite article useful in additive manufacturing, the composite article comprising:
(a) an optional base; (b) at least one three-dimensional lattice support connected to said base (when present); (c) at least one three-dimensional object, the object having a bottom surface portion, a top surface portion, at least one upright segment, and optionally at least one overhanging segment; (d) interconnecting supports connecting (i) each said at least one overhanging segment to said three-dimensional lattice and/or (ii) each at least one upright segment to said three-dimensional lattice; and (e) optionally, a plurality of elongate stand-off supports interconnecting said bottom surface portion of each said three-dimensional object to said base; wherein said composite article is a green intermediate produced by light polymerization of a dual cure resin in an additive manufacturing process.

2 . The composite article of claim 1 , wherein said base is present, and comprises a thin planar segment, optionally configured to promote adhesion of the composite article to an additive manufacturing carrier plate.

3 . The composite article of claim 1 , wherein said stand-off supports are present.

4 . The composite article of claim 1 , wherein said three-dimensional lattice support and said interconnecting supports are configured to inhibit distortion of said at least one three-dimensional object during subsequent heating of said composite article.

5 . The composite article of claim 1 , wherein said at least one three-dimensional object comprises a plurality of separate and distinct three-dimensional objects, all connected to the same said three-dimensional lattice by said interconnecting supports.

6 . The composite article of claim 1 , wherein said additive manufacturing process comprises stereolithography.

7 . The composite article of claim 1 , wherein said additive manufacturing process comprises continuous liquid interface production.

8 . The composite article of claim 1 , wherein said base is adhered to an additive manufacturing carrier plate, and optionally wherein said base has at least one resin flow opening formed therein, said resin flow opening configured to promote flow of resin into said composite article during additive manufacturing thereof, and/or configured to promote flow of wash liquid into and out of said composite article during washing thereof.

9 . The composite article of claim 1 , wherein said lattice support is configured to promote flow of resin into said composite article during additive manufacturing thereof, and/or configured to promote flow of wash liquid into and out of said composite article during washing thereof.

10 . The composite article of claim 1 , wherein said lattice support has at least one enlarged channel formed therein, said enlarged channel configured to further promote flow of resin into said composite article during additive manufacturing thereof, and/or configured to further promote flow of wash liquid into and out of said composite article during washing thereof.

11 . The composite article of claim 1 , wherein:
(i) said composite article is more flexible than the same article following subsequent cure; or (ii) said composite article is less flexible than the same article following subsequent cure thereof.

12 . The composite article of claim 1 , wherein said dual cure resin is comprised of:
(i) light-polymerizable monomers and/or prepolymers that can participate in forming an intermediate object by stereolithography included in an amount of from 5 percent by weight to 80 percent by weight; (ii) heat-polymerizable monomers and/or prepolymers included in an amount of from 5 percent by weight to 60 percent by weight.

13 . The article of claim 12 , wherein:
(iii) said light-polymerizable monomers and/or prepolymers comprise reactive end groups selected from acrylates, methacrylates, α-olefins, N-vinyls, acrylamides, methacrylamides, styrenics, epoxides, thiols, 1,3-dienes, vinyl halides, acrylonitriles, vinyl esters, maleimides, and vinyl ethers; and/or (iv) said heat-polymerizable monomers and/or prepolymers comprise reactive end groups selected from: epoxy/amine, epoxy/hydroxyl, oxetane/amine, oxetane/alcohol, isocyanate/hydroxyl, isocyanate/amine, isocyanate/carboxylic acid, cyanate ester, anhydride/amine, amine/carboxylic acid, amine/ester, hydroxyl/carboxylic acid, hydroxyl/acid chloride, amine/acid chloride, vinyl/Si-H, Si-Cl/hydroxyl, hydroxyl/aldehyde, amine/aldehyde, hydroxymethyl or alkoxymethyl amide/alcohol, aminoplast, alkyne/azide, click chemistry reactive groups, alkene/sulfur, alkene/thiol, alkyne/thiol, hydroxyl/halide, isocyanate/water, Si-OH/hydroxyl, Si-OH/water, Si-OH/Si-H, Si-OH/Si-OH, perfluorovinyl, diene/dienophiles, olefin metathesis polymerization groups, olefin polymerization groups for Ziegler-Natta catalysis, and ring-opening polymerization groups, and mixtures thereof.

14 . The composite article of claim 1 , wherein said dual cure resin comprises a light-polymerizable component that degrades upon heating and forms a reactant in heat curing, thereof.

15 . A method of making at least one object, comprising the steps of:
(a) providing a composite article, the composite article comprising:
(i) an optional base;
(ii) at least one three-dimensional lattice support connected to said base (when present);
(iii) at least one three-dimensional object, the object having a bottom surface portion, a top surface portion, at least one upright segment, and optionally at least one overhanging segment; (iv) interconnecting supports connecting (i) each said at least one overhanging segment to said three-dimensional lattice and/or (ii) each at least one upright segment to said three-dimensional lattice; and (v) optionally, a plurality of elongate stand-off supports interconnecting said bottom surface portion of each said three-dimensional object to said base; wherein said composite article is a green intermediate produced by light polymerization of a dual cure resin in an additive manufacturing process; (b) optionally washing said object; then (c) further curing said composite article; and then (d) separating each said object from said interconnecting supports, and from said stand-off supports if present, to produce said at least one object.

16 . The method of claim 15 , wherein said further curing step is carried out by heating.

17 . The method of claim 15 , wherein said wash step is included and is carried out by immersing said composite article in a wash liquid, with agitation, optionally wherein said wash step is carried out in a time of 10 minutes or less.

18 . The method of claim 15 , wherein said further curing step either:
(i) increases the flexibility of said composite article, or (ii) decreases the flexibility of said composite article.

19 . The method of claim 15 , wherein said further curing step is carried out under conditions in which said least one object is made less frangible than said interconnecting supports.

20 . The method of claim 15 , wherein said further curing step is carried out under conditions in which said three-dimensional lattice support is made less frangible than said interconnecting supports.

Assignees

• Carbon Inc

Inventors

• Barth Florian Markus

Classifications

• B33Y10/00

  Processes of additive manufacturing · CPC title

• B29C64/40 Primary

  Structures for supporting 3D objects during manufacture and intended to be sacrificed after completion thereof · CPC title

• B29C64/135

  the energy source being concentrated, e.g. scanning lasers or focused light sources · CPC title

• A61C7/08

  Mouthpiece-type retainers {or positioners, e.g. for both the lower and upper arch (arch-shaped medicament applicators for teeth or gums A61C19/063; mouthguards for protecting the teeth of sportsmen A63B71/085)} · CPC title