US 12,090,683 B2
Composite transparent film, preparation method thereof, and method for continuous digital light processing ceramic 3D printing based on the same
Guangming Zhang, Shandong (CN); Jin Jiang, Shandong (CN); Hongbo Lan, Shandong (CN); Fei Wang, Shandong (CN); Daosen Song, Shandong (CN); Hui Huang, Shandong (CN); Wenhai Li, Shandong (CN); and Zun Yu, Shandong (CN)
Assigned to QINGDAO UNIVERSITY OF TECHNOLOGY, Qingdao (CN)
Filed by QINGDAO UNIVERSITY OF TECHNOLOGY, Shandong (CN)
Filed on Jan. 4, 2022, as Appl. No. 17/568,098.
Claims priority of application No. 202110011236.5 (CN), filed on Jan. 5, 2021.
Prior Publication US 2022/0212362 A1, Jul. 7, 2022
Int. Cl. B33Y 10/00 (2015.01); B28B 1/00 (2006.01); B28B 13/02 (2006.01); B33Y 40/10 (2020.01); B33Y 70/10 (2020.01)
CPC B28B 1/001 (2013.01) [B28B 1/008 (2013.01); B28B 13/0275 (2013.01); B33Y 10/00 (2014.12); B33Y 40/10 (2020.01); B33Y 70/10 (2020.01)] 8 Claims
OG exemplary drawing
 
1. A method for preparing a composite transparent film for continuous digital light processing ceramic 3D printing, the method comprising steps of:
(1) taking a spherical SiO2 particle with a particle size of about 200 nm and a premixed solution of PDMS, with a mass ratio of SiO2 of 10%-40%, and stirring at 200 r/min-300 r/min for 2-5 min;
(2) mixing a mixed solution of step (1) in an ultrasonic cleaning machine for 15-20 min;
(3) adding a PDMS curing agent after standing and cooling, with the mass ratio of curing agent and a premixed solution of PDMS of 1/10-1/8, and stirring at 200 r/min-300 r/min for 3-5 min;
(4) standing for 12-24 h at a temperature of 0-8° C. until no bubbles;
(5) using a CNC engraving machine to print the mixed solution of step (4) into a film by baseboard heating at 80-100° C. under an air pressure of 30-50 kPa, and a speed of 320-400 mm/s;
(6) drying the printed film in a drying oven;
(7) immersing a fully cured SiO2/PDMS composite film into a container filled with a SiO2 suspension, wherein the particle size of SiO2 in the suspension is 2-5 μm, and pulling up vertically using a pulling machine at a uniform speed of 1-8 mm/s;
(8) heating the resulting composite film of step (7) at 200-250° C. for 60-80 h;
(9) spin-coating a photoresist SU-8-based epoxy resin into a gap between SiO2 particles on a surface of the composite film using a spin coater for 30-60 s at a rotation speed of 2500-3500 r/min, and then using an organic solvent to clean a remaining photoresist on the surface;
(10) curing the photoresist on the surface using a UV curing lamp for 1-3 min; and
(11) etching the resulting composite film of step (10) in a hydrofluoric acid solution for 5-15 min to remove SiO2 on the surface, cleaning thoroughly with alcohol, and drying in the drying oven.