US 11,718,017 B2
Printing method for FDM printing smooth surfaces of items
Rifat Ata Mustafa Hikmet, Eindhoven (NL); and Paulus Albertus Van Hal, Waalre (NL)
Assigned to SIGNIFY HOLDING B.V., Eindhoven (NL)
Appl. No. 17/272,617
Filed by SIGNIFY HOLDING B.V., Eindhoven (NL)
PCT Filed Aug. 30, 2019, PCT No. PCT/EP2019/073225
§ 371(c)(1), (2) Date Mar. 1, 2021,
PCT Pub. No. WO2020/048889, PCT Pub. Date Mar. 12, 2020.
Claims priority of application No. 18192205 (EP), filed on Sep. 3, 2018.
Prior Publication US 2021/0339463 A1, Nov. 4, 2021
Int. Cl. B29C 64/118 (2017.01); B33Y 10/00 (2015.01); B33Y 40/00 (2020.01); B33Y 70/00 (2020.01); B29C 64/245 (2017.01); B29C 64/209 (2017.01); B29C 64/336 (2017.01); B33Y 80/00 (2015.01); B29K 101/12 (2006.01)
CPC B29C 64/118 (2017.08) [B29C 64/209 (2017.08); B29C 64/245 (2017.08); B29C 64/336 (2017.08); B33Y 10/00 (2014.12); B33Y 40/00 (2014.12); B33Y 70/00 (2014.12); B29K 2101/12 (2013.01); B29K 2995/0073 (2013.01); B33Y 80/00 (2014.12)] 9 Claims
OG exemplary drawing
 
1. A method for producing a 3D item by means of fused deposition modelling, the method comprising:
a 3D printing stage comprising layer-wise depositing an extrudate comprising 3D printable material, wherein during at least part of the 3D printing stage the extrudate comprises a core-shell extrudate comprising a core comprising a core material, and a shell comprising a shell material, to provide the 3D item comprising 3D printed material, wherein the 3D item comprises a plurality of layers of 3D printed material, wherein one or more of layers comprises one or more core-shell layer parts, wherein each of the core-shell layer parts comprises a layer core comprising the core material, and a layer shell comprising the shell material, wherein the 3D item has an item surface defined by at least part of the 3D printed material;
an exposure stage comprising exposing at least part of the item surface to a liquid, wherein the core material has core material solubility SC1 for the liquid and wherein the shell material has a shell material solubility SS1 for the liquid, wherein SC1<SS1, wherein:
the core material comprises one or more of polycarbonate (PC), polyethylene (PE), high-density polyethylene (HDPE), polypropylene (PP), polyoxymethylene (POM), polyethylene naphthalate (PEN), styrene-acrylonitrile resin (SAN), polysulfone (PSU), polyphenylene sulfide (PPS), and semi-crystalline polytethylene terephthalate (PET); and
the shell material comprises one or more of acrylonitrile butadiene styrene (ABS), poly(methyl methacrylate) (PMMA), polystyrene (PS), and styrene acrylic copolymers (SMMA).