US 11,833,851 B2
Microsphere articles and transfer articles
Vivek Krishnan, St. Paul, MN (US); John C. Clark, Maplewood, MN (US); Thomas B. Galush, Roseville, MN (US); and Jean A. Tangeman, Minneapolis, MN (US)
Assigned to 3M Innovative Properties Company, St. Paul, MN (US)
Filed by 3M INNOVATIVE PROPERTIES COMPANY, St. Paul, MN (US)
Filed on Sep. 9, 2020, as Appl. No. 17/015,466.
Application 17/015,466 is a continuation of application No. 14/379,027, abandoned, previously published as PCT/US2013/026781, filed on Feb. 20, 2013.
Claims priority of provisional application 61/601,832, filed on Feb. 22, 2012.
Prior Publication US 2020/0398608 A1, Dec. 24, 2020
Int. Cl. B44C 1/17 (2006.01); B32B 27/20 (2006.01); B32B 7/12 (2006.01); B32B 27/14 (2006.01); B32B 27/02 (2006.01); B32B 27/08 (2006.01); G02B 5/128 (2006.01); B44C 3/02 (2006.01); B44C 1/10 (2006.01)
CPC B44C 1/1737 (2013.01) [B32B 7/12 (2013.01); B32B 27/02 (2013.01); B32B 27/08 (2013.01); B32B 27/14 (2013.01); B32B 27/20 (2013.01); B44C 1/105 (2013.01); B44C 3/02 (2013.01); G02B 5/128 (2013.01); B32B 2260/025 (2013.01); B32B 2260/046 (2013.01); B32B 2264/101 (2013.01); B32B 2307/402 (2013.01); B32B 2405/00 (2013.01); B32B 2451/00 (2013.01); B32B 2509/00 (2013.01); Y10T 428/1405 (2015.01); Y10T 428/24372 (2015.01); Y10T 428/24405 (2015.01); Y10T 428/24421 (2015.01); Y10T 428/25 (2015.01)] 21 Claims
OG exemplary drawing
 
1. An article comprising at least a first surface having:
(a) a first binder layer;
(b) a plurality of transparent microspheres partially embedded in the first binder layer such that about 20% to about 70% of the average diameter of the transparent microspheres is exposed at the outermost surface of the article and wherein at least 70% by count of the transparent microspheres in the plurality of transparent microspheres are free of bubble defects;
wherein the plurality of transparent microspheres consists of microspheres having a refractive index of no more than 1.490, and
wherein the plurality of transparent microspheres consists of microspheres having a refractive index at least 0.042 less than the refractive index of the first binder layer.