# US 8,786,936 B2 · Ink compositions, methods of preparing ink compositions and display panels including ink compositions > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,786,936 B2 - Document ID: US8786936B2 - Status: Granted - Kind: B2 - Application number: 13/623,369 - Filed: 2012-09-20 - Published: 2013-07-04 - Granted: 2014-07-22 - Earliest claimed: 2011-12-29 - Assignees: Noroo Holdings Co., Ltd. - Applicants: Jung-II Kong; Jung-Sok Noh; Hoon Cheong; Deok-Min Park; Hee-Jong Kim; Jin-Hwan Jung; Cheol-Woo Kim - Inventors: Jung-II Kong; Jung-Sok Noh; Hoon Cheong; Deok-Min Park; Hee-Jong Kim; Jin-Hwan Jung; Cheol-Woo Kim - Web page: https://patentgrep.com/patent/US8786936B2 ## CPC - C09C 3/12: Treatment with organosilicon compounds {(C09C3/006 takes precedence)} - C09C 3/08: Treatment with low-molecular-weight {non-polymer} organic compounds {(C09C3/006, C09C3/048 take precedence)} - C09D 11/037: characterised by the pigment - C01P 2004/62: Submicrometer sized, i.e. from 0.1-1 micrometer - C01P 2004/84: one phase coated with the other - C01P 2006/40: Electric properties - C01P 2006/60: Optical properties, e.g. expressed in CIELAB-values - G02F 2001/1678: {characterised by the composition or particle type} - C09C: TREATMENT OF INORGANIC MATERIALS, OTHER THAN FIBROUS FILLERS, TO ENHANCE THEIR PIGMENTING OR FILLING PROPERTIES (treatment of materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone C04B14/00, C04B18/00, C04B20/00); PREPARATION OF CARBON BLACK {; PREPARATION OF INORGANIC MATERIALS WHICH ARE NO SINGLE CHEMICAL COMPOUNDS AND WHICH ARE MAINLY USED AS PIGMENTS OR FILLERS} - C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D) - C01P: INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS - G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS ## Abstract Core-shell coated pigment particles are prepared by core-shell coating using pigment particles, at least one hydrophilic organometallic compound, at least one hydrophobic organometallic compound, distilled water and a solvent. Ink particles coated with an ionized organometallic compound are prepared by using the core-shell coated pigment particles, the solvent and a halogen compound. The ink particles, a dispersing agent and a dielectric liquid are mixed to prepare an ink composition. The ink composition has an electrophoresis property to exhibit an electric movement and has a good dispersibility in a dielectric liquid. The ink composition may be applied in a reflective type color display device. ## Claims ### Claim 1 An ink composition comprising: ink particles core-shell coated with at least one ionized hydrophilic organometallic compound and at least one hydrophobic organometallic compound; a dispersing agent; and a dielectric liquid. ### Claim 2 (depends on 1) The ink composition of claim 1, wherein the ink composition includes about 30 to 70 percent by weight of the ink particles, about 10 to 20 percent by weight of the dispersing agent and about 10 to 50 percent by weight of the dielectric liquid. ### Claim 3 (depends on 1) The ink composition of claim 1, wherein the ink particles include at least one electronic ink particles selected from the group consisting of white ink particles, black ink particles, red-colored ink particles, green-colored ink particles and blue-colored ink particles. ### Claim 4 (depends on 1) The ink composition of claim 1, wherein the organometallic compound includes at least one metal atom or metalloid atom. ### Claim 5 A method of preparing an ink composition, comprising: preparing core-shell coated pigment particles by core-shell coating using pigment particles, at least one hydrophilic organometallic compound, at least one hydrophobic organometallic compound, distilled water and a solvent; preparing ink particles coated with an ionized organometallic compound by using the core-shell coated pigment particles, the solvent and a halogen compound; and mixing the ink particles, a dispersing agent and a dielectric liquid. ### Claim 6 (depends on 5) The method of claim 5, wherein about 30 to 70 percent by weight of the pigment particles, about 10 to 30 percent by weight of the hydrophilic organometallic compound, about 5 to 20 percent by weight of the hydrophobic organometallic compound, about 10 to 40 percent by weight of the distilled water and about 30 to 50 percent by weight of the solvent are used. ### Claim 7 (depends on 5) The method of claim 5, wherein the ink particles coated with the ionized organometallic compound are prepared by using about 30 to 50 percent by weight of the core-shell coated pigment particles, about 20 to 50 percent by weight of the solvent and about 10 to 30 percent by weight of the halogen compound. ### Claim 8 (depends on 5) The method of claim 5, wherein about 30 to 70 percent by weight of the ink particles, about 10 to 20 percent by weight of the dispersing agent and about 10 to 50 percent by weight of the dielectric liquid are used in the mixing step. ### Claim 9 (depends on 5) The method of claim 5, wherein the core-shell coated pigment particles are prepared by using a sol-gel process at a surface portion of the pigment particles. ### Claim 10 (depends on 5) The method of claim 5, wherein the ink particles include at least one electronic ink particles selected from the group consisting of white ink particles, black ink particles, red-colored ink particles, green-colored ink particles and blue-colored ink particles. ### Claim 11 (depends on 5) The method of claim 5, wherein the hydrophilic organometallic compound includes at least one compound for imparting a positive charge, selected from the group consisting of aminopropyl trimethoxy silane, aminopropyl triethoxysilane, aminopropylmethyl diethoxysilane, m-aminophenyl trimethoxysilane, n-methyl aminopropylmethyl dimethoxysilane, phenyl aminopropyl trimethoxysilane, aminoethyl aminopropyl trimethoxysilane, aminoethyl aminopropylmethyl dimethoxysilane, aminoethyl aminoisobutylmethyl dimethoxysilane, benzylethyl diaminopropyl trimethoxysilane and benzylethyl diaminopropyl triethoxysilane, or at least one compound for imparting a negative charge, selected from the group consisting of sodium trihydroxysilylpropylmethyl phosphonate, sodium methyl siliconate, potassium methyl siliconate, lithium methyl siliconate, sodium silicate, potassium silicate and titanium phosphate. ### Claim 12 (depends on 5) The method of claim 5, wherein the hydrophobic organometallic compound includes at least one selected from the group consisting of methyl trimethoxysilane, dimethyl trimethoxysilane, tetraorthosilicate and hydroxyl terminated polydimethylsiloxane. ### Claim 13 (depends on 12) The method of claim 12, wherein a weight mean molecular weight of the hydroxyl terminated polydimethylsiloxane is in a range of about 500 to 5,000. ### Claim 14 (depends on 5) The method of claim 5, wherein the halogen compound includes at least one selected from the group consisting of methyl chloride, ethyl chloride, butyl chloride, pentyl chloride, hexyl chloride, heptyl chloride, octenyl chloride, noneyl chloride, decanyl chloride, benzyl chloride, methyl sulfonate, ethyl sulfonate, butyl sulfonate and pentyl sulfonate. ### Claim 15 A mixed color ink composition comprising: a first ink composition including first ink particles core-shell coated with at least one ionized hydrophilic organometallic compound and at least one hydrophobic organometallic compound, a dispersing agent and a dielectric liquid; a second ink composition including second ink particles core-shell coated with at least one ionized hydrophilic organometallic compound and at least one hydrophobic organometallic compound, the dispersing agent and the dielectric liquid; and a low dielectric liquid. ### Claim 16 (depends on 15) The mixed color ink composition of claim 15, wherein the mixed color ink composition includes about 10 to 50 percent by weight of the first ink composition, about 10 to 50 percent by weight of the second ink composition and about 30 to 80 percent by weight of the low dielectric liquid. ### Claim 17 A display panel comprising: a substrate including a cell structure defined by partitioned walls; and an ink composition sealed in the cell structure, the ink composition including ink particles core-shell coated with at least one ionized hydrophilic organometallic compound and at least one hydrophobic organometallic compound, a dispersing agent and a dielectric liquid. ### Claim 18 A display panel comprising: a substrate including a cell structure defined by partitioned walls; and a mixed color ink composition sealed in the cell structure, the mixed color ink composition including a first single color ink composition obtained by dispersing uniformly ink particles core-shell coated with at least one ionized hydrophilic organometallic compound and at least one hydrophobic organometallic compound in a dielectric liquid, and a second single color ink composition having different color from the first single color ink composition. ### Claim 19 A method of manufacturing a display panel, comprising: preparing a first single color ink composition by dispersing uniformly ink particles core-shell coated with at least one ionized hydrophilic organometallic compound and at least one hydrophobic organometallic compound in a dielectric liquid; preparing a second single color ink composition having a different color from the first single color ink composition; preparing a mixed color ink composition by mixing the first and second single color ink compositions; and forming a pixel by injecting the mixed color ink composition into a cell structure.