US 12,084,595 B2
Electrophoretic media including charge control agents comprising quartenary amines and unsaturated polymeric tails
Ziyan Wu, Wayland, MA (US); Jason D. Feick, Auburndale, MA (US); James H. Aborn, Medford, MA (US); John Lock, Wakefield, MA (US); Kosta Ladavac, Somerville, MA (US); Erik Dunkerley, Billerica, MA (US); Hui Du, Milpitas, CA (US); and Olga Vladimirovna Barykina-Tassa, Boston, MA (US)
Assigned to E Ink Corporation, Billerica, MA (US)
Filed by E INK CORPORATION, Billerica, MA (US)
Filed on Jul. 21, 2021, as Appl. No. 17/381,983.
Application 17/381,983 is a continuation of application No. 15/284,887, filed on Oct. 4, 2016, granted, now 11,098,206.
Claims priority of provisional application 62/237,691, filed on Oct. 6, 2015.
Prior Publication US 2021/0355332 A1, Nov. 18, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. C09D 5/44 (2006.01); G02F 1/1675 (2019.01); G02F 1/1681 (2019.01)
CPC C09D 5/4407 (2013.01) [C09D 5/44 (2013.01); C09D 5/4411 (2013.01); C09D 5/4476 (2013.01); C09D 5/448 (2013.01); G02F 2001/1678 (2013.01); G02F 1/1681 (2019.01)] 20 Claims
OG exemplary drawing
 
1. An electrophoretic medium comprising:
(a) a non-polar fluid;
(b) a plurality of first charged particles having a first charge polarity;
(c) a plurality of second charged particles having a second charge polarity; and
(d) a charge control agent comprising a quaternary amine and an unsaturated polymeric tail having at least one carbon-carbon double bond comprising monomers of at least 10 carbon atoms in length, the ratio of charge control agent to first charge particles being greater than 1:500 wt/wt;
wherein the first and second charged particles have opposite polarities and move in opposite directions through the non-polar fluid under the influence of an electric field;
wherein electrophoretic medium is encapsulated in a microcell or a protein coacervate; and
wherein the viscosity of the electrophoretic medium is less than 5×10−2 Pa·s at −30° C., measured with a rheometer having a recessed concentric cylinder using a temperature ramp of 2° C. per minute method.