Electrophoretic Particles Comprising an Organic Pigment and Graphene Oxide
AssigneeE Ink Corporation
InventorSaemi Oh POELMA
Life of this patent
Estimating the term…
Abstract
An electrophoretic medium comprises a plurality of a first type of charged particles in a non-polar liquid. Each of the plurality of the first type of charged particles has a core and a shell. The core comprises an organic pigment and a graphene oxide layer. The shell comprises an organosilane layer and a polymeric layer. The electrophoretic medium may be incorporated in a color electrophoretic device to improve its electro-optic performance.
Claims20
An electrophoretic medium comprising a plurality of a first type of charged particles and a non-polar liquid, each of the plurality of the first type of charged particles having a core and a shell,
- the core comprising a first type of organic pigment having a surface, a graphene oxide layer comprising graphene oxide, the graphene oxide layer being in contact with the surface of the first type of the organic pigment;
- the shell comprising an organosilane layer and a polymeric layer, the organosilane layer comprising an organosilane, and the polymeric layer comprising a polymer, the organosilane of the organosilane layer of the shell being covalently bonded to the polymer of polymeric layer.
A method of manufacturing of an electrophoretic medium comprising a non-polar liquid and a first type of charged particles, the first type of charged particles having a core and a shell, the method of manufacturing comprising the steps:
- providing graphene oxide;
- dispersing the graphene oxide into a polar organic solvent to make a graphene oxide dispersion;
- adding an organic pigment into the graphene oxide dispersion to prepare an organic pigment-graphene oxide dispersion;
- mixing the organic pigment-graphene oxide dispersion to prepare an organic pigment-graphene oxide complex in the polar organic solvent;
- adding a metal oxide precursor and a reagent into the organic pigment-graphene oxide complex in the polar organic solvent to prepare a dispersion of particles comprising organic pigment-graphene oxide complex having a metal oxide layer, the metal oxide layer comprising a metal oxide;
- adding an organosilane reagent into the dispersion of particles comprising the organic pigment-graphene oxide complex having the metal oxide layer to prepare a dispersion having particles comprising the organic pigment-graphene oxide complex having the metal oxide layer and an organosilane layer, the organosilane layer having an organosilane, wherein the organosilane is covalently bonded to the metal oxide;
- separating the particles comprising the organic pigment-graphene oxide complex having the metal oxide layer and an organosilane layer from the polar organic solvent;
- washing the particles comprising the organic pigment-graphene oxide complex having the metal oxide layer and the organosilane layer with a solvent;
- transferring the washed particles comprising the organic pigment-graphene oxide complex having the metal oxide layer and the organosilane layer into a non-polar liquid to prepare a dispersion of particles comprising the organic pigment-graphene oxide complex having the metal oxide layer and the organosilane layer in the non-polar liquid;
- adding a monomer or a macromonomer into the dispersion of particles comprising the organic pigment-graphene oxide complex having the metal oxide layer and the organosilane layer in the non-polar liquid;
- and
- polymerizing the monomer or reacting the macromonomer with the organosilane of the organosilane layer of the particles comprising the organic pigment-graphene oxide complex having the metal oxide layer and the organosilane layer to prepare a dispersion comprising the first type of charged particles in the non-polar liquid, each of the first type of charged particles comprising the organic pigment-graphene oxide complex having the metal oxide layer, the organosilane layer, and a polymeric layer, the polymeric layer comprising a polymer, the polymer being covalently bonded to the organosilane of the organosilane layer.
Dependencies are inferred from the claim text.