US 12,296,527 B2
Dual cure polyurethane formulations for 3D printing applications
Sascha Poeller, Duisburg (DE); Manuel Schiel, Duesseldorf (DE); Tanja Rossberg, Haan (DE); Andreas Ferencz, Duesseldorf (DE); Tim Welters, Hilden (DE); and Uwe Franken, Dormagen (DE)
Assigned to Henkel AG & Co. KGaA, Duesseldorf (DE)
Filed by Henkel AG & Co. KGaA, Duesseldorf (DE)
Filed on Nov. 8, 2021, as Appl. No. 17/453,948.
Application 17/453,948 is a continuation of application No. PCT/EP2020/063157, filed on May 12, 2020.
Claims priority of application No. 19174173 (EP), filed on May 13, 2019.
Prior Publication US 2022/0055285 A1, Feb. 24, 2022
Int. Cl. B29C 64/106 (2017.01); B29C 64/188 (2017.01); B29C 64/209 (2017.01); B29C 64/245 (2017.01); B29C 64/264 (2017.01); B33Y 10/00 (2015.01); B33Y 40/20 (2020.01); B33Y 70/00 (2020.01); B29K 75/00 (2006.01); B29K 105/00 (2006.01)
CPC B29C 64/106 (2017.08) [B29C 64/188 (2017.08); B29C 64/209 (2017.08); B29C 64/245 (2017.08); B29C 64/264 (2017.08); B33Y 10/00 (2014.12); B33Y 40/20 (2020.01); B33Y 70/00 (2014.12); B29K 2075/00 (2013.01); B29K 2105/0002 (2013.01); B29K 2105/0014 (2013.01); B29K 2105/007 (2013.01); B29K 2105/0094 (2013.01)] 9 Claims
 
1. A method for additive manufacturing a three-dimensional part in a layer-by-layer manner, the method comprising:
(i) providing a carrier substrate to support the three-dimensional part and a print head connected to a reservoir of a reactive curable printable composition;
(ii) printing the reactive curable printable composition with the print head as extrudate strands onto the carrier substrate to form a first layer;
(iii) printing the reactive curable printable composition with the print head as extrudate strands onto the first layer to form a second layer;
(iv) optionally repeating step (iii) one or more times to form a third layer or the third layer and subsequent layer(s);
(v) exposing the formed layers to radiation directly after forming each layer and/or after forming all of the layers; and
(vi) curing the formed layers of the reactive curable printable composition to obtain the three-dimensional part,
wherein the reactive curable printable composition is a pasty polyurethane composition comprising:
at least one polyisocyanate resin;
at least one monomer and/or prepolymer that is polymerizable by exposure to radiation; and
at least one photoinitiator, wherein:
the pasty polyurethane composition has a first viscosity factor (1.5/15) of at least 2 and a second viscosity factor (5/50) at an application temperature,
the first viscosity factor (1.5/15) is the viscosity of the pasty polyurethane composition at a shear rate of 1.5/s divided by the viscosity of the pasty polyurethane composition at a shear rate of 15/s and the second viscosity factor (5/50) is the viscosity of the pasty polyurethane composition at a shear rate of 5/s divided by the viscosity of the pasty polyurethane composition at a shear rate of 50/s,
the pasty polyurethane composition has a viscosity at a shear rate of 1.5/s of at least 10 Pas, and
the first viscosity factor (1.5/15) is greater than the second viscosity factor (5/50).