US 12,117,635 B2
Optical stack
Michelle L. Toy, North St. Paul, MN (US); Kristy A. Gillette, Spring Valley, WI (US); Matthew B. Johnson, Woodbury, MN (US); Eileen M. Franey, Woodbury, MN (US); Carley A. Haroldson, Centerville, MN (US); Joseph P. Attard, Woodbury, MN (US); Guy M. Kallman, Woodbury, MN (US); and William Blake Kolb, Stillwater, MN (US)
Assigned to 3M INNOVATIVE PROPERTIES COMPANY, St. Paul, MN (US)
Appl. No. 17/438,245
Filed by 3M INNOVATIVE PROPERTIES COMPANY, St. Paul, MN (US)
PCT Filed Apr. 28, 2020, PCT No. PCT/IB2020/053987
§ 371(c)(1), (2) Date Sep. 10, 2021,
PCT Pub. No. WO2020/222117, PCT Pub. Date Nov. 5, 2020.
Claims priority of provisional application 62/840,681, filed on Apr. 30, 2019.
Prior Publication US 2022/0187521 A1, Jun. 16, 2022
Int. Cl. G02B 27/01 (2006.01); G02B 5/30 (2006.01)
CPC G02B 5/305 (2013.01) [G02B 27/0101 (2013.01); G02B 2027/012 (2013.01)] 15 Claims
OG exemplary drawing
 
1. An optical stack comprising:
an optical film comprising a plurality of alternating first and second polymeric layers numbering at least 50 in total, each first and second polymeric layer having an average thickness less than about 500 nm; and
an optical adhesive disposed on the optical film and comprising a first major surface facing and bonded to the optical film, and an opposing second major structured surface comprising a plurality of irregularly arranged intersecting channels formed therein, the channels defining a plurality of substantially flat land regions therebetween, the land regions comprising at least about 50% of a total surface area of the second major structured surface, such that when the optical stack is placed on a support surface with the second major structured surface of the optical adhesive contacting the support surface, the optical stack bonds to the support surface and may be removed from, or slidingly repositioned on, the support surface without damage to the optical adhesive or the support surface, and upon application of at least one of heat and pressure, the optical stack substantially permanently bonds to the support surface and the plurality of channels substantially disappear.