US 11,878,461 B2
Core-shell filament for use in extrusion-based additive manufacturing systems and method of printing parts
William J. Swanson, St. Paul, MN (US); and William R. Priedeman, Jr., Long Lake, MN (US)
Assigned to Stratasys, Inc., Eden Prairie, MN (US)
Appl. No. 17/290,852
Filed by Stratasys, Inc., Eden Prarie, MN (US)
PCT Filed Nov. 4, 2019, PCT No. PCT/US2019/059676
§ 371(c)(1), (2) Date May 3, 2021,
PCT Pub. No. WO2020/093049, PCT Pub. Date May 7, 2020.
Claims priority of provisional application 62/754,986, filed on Nov. 2, 2018.
Prior Publication US 2021/0387402 A1, Dec. 16, 2021
Int. Cl. B29C 64/118 (2017.01); D01F 8/12 (2006.01); D01F 8/14 (2006.01); B33Y 10/00 (2015.01); B33Y 70/10 (2020.01); B29K 21/00 (2006.01); B29K 77/00 (2006.01)
CPC B29C 64/118 (2017.08) [D01F 8/12 (2013.01); D01F 8/14 (2013.01); B29K 2021/003 (2013.01); B29K 2077/00 (2013.01); B29K 2995/0046 (2013.01); B33Y 10/00 (2014.12); B33Y 70/10 (2020.01)] 29 Claims
OG exemplary drawing
1. A filament for use in an extrusion-based additive manufacturing system, the filament comprising:
a core compositionally comprising an elastomeric core material having a flexural modulus of less than 31,000 psi and a durometer of less than 80 Shore A; and
a shell covering the core and having a thickness t, the shell compositionally comprising a non-elastomeric thermoplastic shell material that is substantially miscible with the elastomeric core material and has the same monomer chemistry as the elastomeric core material, and wherein the non-elastomeric thermoplastic shell material has a flexural modulus that is at least five times greater than the flexural modulus of the elastomeric core material,
wherein the shell provides sufficient stiffness to the filament such that filament can be utilized as a feedstock in the extrusion-based additive manufacturing system.