US 11,806,795 B2
Security articles comprising groups of microstructures made by end milling
Nelson D. Sewall, Forest Lake, MN (US); and Christopher S. Grinde, Baldwin, WI (US)
Assigned to 3M INNOVATIVE PROPERTIES COMPANY, St. Paul, MN (US)
Appl. No. 16/485,085
Filed by 3M INNOVATIVE PROPERTIES COMPANY, St. Paul, MN (US)
PCT Filed Feb. 5, 2018, PCT No. PCT/US2018/016851
§ 371(c)(1), (2) Date Aug. 9, 2019,
PCT Pub. No. WO2018/151964, PCT Pub. Date Aug. 23, 2018.
Claims priority of provisional application 62/527,511, filed on Jun. 30, 2017.
Claims priority of provisional application 62/515,993, filed on Jun. 6, 2017.
Claims priority of provisional application 62/458,812, filed on Feb. 14, 2017.
Prior Publication US 2023/0201932 A1, Jun. 29, 2023
Int. Cl. B23C 5/10 (2006.01); B23C 3/10 (2006.01); G02B 5/124 (2006.01)
CPC B23C 5/10 (2013.01) [B23C 3/10 (2013.01); G02B 5/124 (2013.01); B23C 2265/08 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An article, comprising:
a substrate having a structured surface that extends along a reference plane, the structured surface including distinct microstructures formed therein, each of the microstructures being a recess or a protrusion;
wherein each of the microstructures has a first face, and a second face distinct from the first face, that connect to each other by a rounded edge, the rounded edge extending along an axis that is inclined at an angle α relative to the reference plane; and
wherein the microstructures comprise first microstructures and second microstructures that differ from each other to define indicia.