Printable compositions including highly viscous components and methods of creating 3D articles therefrom
The present disclosure provides a method for building a three-dimensional object using a printable composition including high viscosity polymerizable components. The method includes the steps of a) providing a printable composition comprising a high viscosity polymerizable component and a temporary solvent; b) selectively curing the printable composition to form an article representing the shape of the three-dimensional object; and c) removing a substantial amount of the temporary solvent from the article. The method is particularly well suited to making an orthodontic clear tray aligner. Also disclosed are a variety of printable compositions including high viscosity polymerizable components, such as polyurethane methacrylates, and temporary solvents.
1. A method for building a three-dimensional object, the method comprising:
a) providing a printable composition comprising 45 to 95 wt. % of a high viscosity polymerizable component, 10 to 40 wt. % of a temporary solvent, and 0.1 to 5 wt. % of an initiator, based on the total weight of the printable composition, wherein the high viscosity polymerizable component has a viscosity of at least 20,000 cP at 25° C. before mixing with the temporary solvent;
b) selectively curing the printable composition in a layer-by-layer manner to form an article from a plurality of layers of the printable composition, the article representing the shape of the three-dimensional object;
c) removing a substantial amount of the temporary solvent from the article;
and d) optionally curing unpolymerized polymerizable component remaining before or after step c).
2. The method of claim 1 , wherein the printable composition has a viscosity no greater than 15,000 cP at 25° C., no greater than 10,000 cP at 25° C., or no greater than 5,000 cP at 25° C.
3. The method of claim 1 , wherein the temporary solvent is nonreactive in the printable composition resin and constitutes 10 to 110 wt. %, based on weight of the total printable composition or 15 to 30 wt. %, based on weight of the total printable composition.
4. The method of claim 1 , wherein removing a substantial amount of the temporary solvent comprises removing at least 60% of the temporary solvent, at least 90% of the temporary solvent, or at least 95% of the temporary solvent.
5. The method of claim 1 , wherein removing a substantial amount of the temporary solvent comprises heating the article at a temperature above 25° C. and below 90° C. for at least 12 hours.
6. The method of claim 1 , wherein removing a substantial amount of the temporary solvent comprises immersing the article in water for at least 12 hours; removing the article from the water; and allowing the article to dry at ambient temperature.
7. The method of claim 1 , wherein the high viscosity polymerizable component has a viscosity of at least 30,000 cP and no greater than 300,000 cP at 25° C. before mixing with the temporary solvent.
8. The method of claim 1 , wherein the high viscosity polymerizable component comprises a poly(meth)acrylate.
9. The method of claim 8 , wherein the high viscosity polymerizable component comprises one or more multi-functional urethane (meth)acrylates.