Support material formulation and additive manufacturing processes employing same

Patent metadata

Field	Value
Publication number	US-11850802-B2
Application number	US-202117542549-A
Country	US
Kind code	B2
Filing date	Dec 6, 2021
Priority date	Aug 14, 2015
Publication date	Dec 26, 2023
Grant date	Dec 26, 2023

Abstract

Novel support material formulations, characterized as providing a cured support material with improved dissolution rate, while maintaining sufficient mechanical strength, are disclosed. The formulations comprise a water-miscible non-curable polymer, a first water-miscible, curable material and a second, water-miscible material that is selected capable of interfering with intermolecular interactions between polymeric chains formed upon exposing the first water-miscible material to curing energy. Methods of fabricating a three-dimensional object, and a three-dimensional object fabricated thereby are also disclosed.

First claim

What is claimed is:

1. A support material formulation comprising:
a non-curable water-miscible polymer, in an amount that ranges from 30 to 80 weight percent of the total weight of the formulation, said non-curable water-miscible polymer comprising an alkoxylated polyol;
a non-curable water-miscible non-polymeric material which comprises 1,2-propanediol;
a first water-miscible, curable material in an amount that ranges from 10 to 20 weight percent of the total weight of the formulation; and
at least one second water-miscible curable material in an amount that ranges from 5 to 15 weight percent of the total weight of the formulation,
wherein said first water-miscible curable material comprises a mono-functional poly(alkylene glycol) acrylate; and
wherein said second water-miscible curable material is represented by Formula I:

wherein:
Ra is selected from H, C(1-4) alkyl and a hydrophilic group;
k is an integer ranging from 2 to 10;
X is —NRc—, wherein Rc is hydrogen, alkyl, cycloalkyl or aryl; and
Y is a hydrogen bond-forming moiety that comprises at least one nitrogen and/or oxygen atom,
the formulation being devoid of a multi-functional curable material.

2. The formulation of claim 1 , wherein said second water-miscible curable material is an acrylamide substituted by said hydrogen bond-forming moiety.

3. The formulation of claim 1 , wherein Y is selected from hydroxyl, alkoxy, aryloxy, amine, alkylamine, dialkylamine, carboxylate, hydrazine, carbamate, hydrazine, a nitrogen-containing heteralicyclic, and an oxygen-containing heteralicyclic.

4. The formulation of claim 3 , wherein X is —O—.

5. The formulation of claim 4 , wherein Ra is H, such that the second curable material is an acrylate.

6. The formulation of claim 1 , wherein Ra is H, such that the second curable material is an acrylamide.

7. The formulation of claim 1 , wherein said water-miscible polymer comprises said alkoxylated polyol and a polyethylene glycol.

8. The formulation of claim 1 , wherein a concentration of said second water-miscible curable material ranges from 5 to 10 weight percent of the total weight of the formulation.

9. The formulation of claim 1 , further comprising an initiator, a surface active agent and/or an inhibitor.

10. The formulation of claim 1 , wherein each of said first and second water-miscible curable materials is a UV-curable material.

11. The formulation of claim 1 , wherein a cured support material formed upon exposing the formulation to a curing energy is dissolvable in an alkaline solution.

12. The formulation of claim 11 , wherein a dissolution time of a cured support material when immersed in said alkaline solution is at least 2-folds, or at least 4-folds, shorter than a dissolution time of a cured support material made of a comparable support material formulation that is absent said second water-miscible curable material.

13. The formulation of claim 11 , wherein a dissolution time of a 16-grams cube made of said cured support material and immersed in 800 ml of said alkaline solution is less than 2 hours.

14. The formulation of claim 1 , wherein a cured support material formed upon exposing the formulation to a curing energy is characterized by a mechanical strength that is lower than a mechanical strength of a cured support material made of a comparable support material formulation that is absent said second water-miscible curable material and comprises substantially the same total concentration of curable materials as the formulation, by no more than 50% or by no more than 40%, or by no more than 30%.

Assignees

• Stratasys Ltd

Inventors

• Vidavsky Yuval
• Peri Dani
• Pokrass Mariana
• Levy Avraham
• Matzner Eynat

Classifications

• B29C64/40 Primary

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

• B29C64/112

  using individual droplets, e.g. from jetting heads · CPC title

• B29C64/35 Primary

  Cleaning · CPC title

• B33Y10/00

  Processes of additive manufacturing · CPC title

• B33Y40/20

  Post-treatment, e.g. curing, coating or polishing · CPC title