# US 2017/0287993 A1 · Display panel and method for manufacturing same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0287993 A1 - Document ID: US20170287993A1 - Status: Published application - Kind: A1 - Application number: 15/471,286 - Filed: 2017-03-28 - Published: 2017-10-05 - Earliest claimed: 2016-03-31 - Assignees: Joled Inc.; Japan Display Inc. - Applicants: Joled Inc.; Japan Display Inc. - Inventors: Masakazu TAKATA - Web page: https://patentgrep.com/patent/US20170287993A1 ## CPC - H10K 59/35: comprising red-green-blue [RGB] subpixels - H10K 59/122: Pixel-defining structures or layers, e.g. banks - H10K 71/135: {using ink-jet printing} - H10K 71/191: {characterised by provisions for the orientation or alignment of the layer to be deposited} - H10K 50/15: Hole transporting layers - H10K 50/16: Electron transporting layers - H10K 50/17: Carrier injection layers - H10K 50/171: {Electron injection layers} - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES ## Abstract A display panel including a substrate; first, second, and third lower electrodes; first and second column banks; first, second, and third organic light-emitting layers; and an upper electrode. When a first ink for forming the first organic light-emitting layer, a second ink for forming the second organic light-emitting layer, and a third ink for forming the third organic light-emitting layer are applied, ink-separating capability of the first column bank for separating the first ink and the second ink is lower than ink-separating capability of the second column bank for separating the second ink and the third ink, and ink-separating capability depends on: (i) a height of the first and second column banks, or (ii) liquid repellency of the first column bank against the first ink and the second ink and liquid repellency of the second column bank against the second ink and the third ink. ## Claims ### Claim 1 A method of manufacturing a display panel, comprising: preparing a substrate; forming, on the substrate, a first lower electrode, a second lower electrode, and a third lower electrode that are spaced away from one another in a first direction; forming a first column bank between the first lower electrode and the second lower electrode, and a second column bank between the second lower electrode and the third lower electrode; applying a first ink containing a first organic light-emitting material above the first lower electrode, a second ink containing a second organic light-emitting material above the second lower electrode, and a third ink containing a third organic light-emitting material above the third lower electrode; forming a first organic light-emitting layer by drying the first ink, forming a second organic light-emitting layer by drying the second ink, and forming a third organic light-emitting layer by drying the third ink; and forming an upper electrode covering the first organic light-emitting layer, the second organic light-emitting layer, the third organic light-emitting layer, the first column bank, and the second column bank, wherein the second organic light-emitting material has the same light-emission color as the light-emission color of the first organic light-emitting material, and the third organic light-emitting material has a light-emission color that is different from the light-emission color of the first organic light-emitting material. ### Claim 2 (depends on 1) The method of claim 1, wherein when applying the first ink, the second ink, and the third ink, the first ink and the second ink each spread onto the first column bank and contact each other. ### Claim 3 (depends on 1) The method of claim 1, wherein a height of the first column bank is lower than a height of the second column bank. ### Claim 4 (depends on 1) The method of claim 1, wherein liquid repellency of the first column bank against the first ink and the second ink is lower than liquid repellency of the second column bank against the second ink and the third ink. ### Claim 5 (depends on 1) The method of claim 1, wherein a width of the first column bank in the first direction is smaller than a width of the second column bank in the first direction. ### Claim 6 (depends on 1) The method of claim 1, wherein a volume of the third ink applied per unit area is smaller than a volume of the first ink applied per unit area and a volume of the second ink applied per unit area. ### Claim 7 (depends on 1) The method of claim 1, wherein viscosity of the third ink is higher than viscosity of the first ink and viscosity of the second ink. ### Claim 8 (depends on 1) The method of claim 1, wherein applying of the first ink, the second ink, and the third ink is performed through ejecting the first ink, the second ink, and the third ink from an ink-jet device, and upon ejection from the ink-jet device, a ligament of the third ink is shorter than a ligament of the first ink and a ligament of the second ink. ### Claim 9 A display panel comprising: a substrate; a first lower electrode, a second lower electrode, and a third lower electrode that are disposed on the substrate and are spaced away from one another in a first direction; a first column bank disposed above the substrate and between the first lower electrode and the second lower electrode, and extending in a second direction intersecting the first direction; a second column bank disposed above the substrate and between the second lower electrode, and the third lower electrode and extending in the second direction; a first organic light-emitting layer disposed above the first lower electrode, a second organic light-emitting layer disposed above the second lower electrode, and a third organic light-emitting layer disposed above the third lower electrode; and an upper electrode disposed above the first organic light-emitting layer, the second organic light-emitting layer, the third organic light-emitting layer, the first column bank, and the second column bank, wherein the first organic light-emitting layer contains a first organic light-emitting material, the second organic light-emitting layer contains a second organic light-emitting material that has the same light-emission color as the first organic light-emitting material, the third organic light-emitting layer contains a third organic light-emitting material that has a light-emission color that is different from the first organic light-emitting material, ink-separating capability of the first column bank for separating a first ink and a second ink is lower than ink-separating capability of the second column bank for separating the second ink and a third ink, the first ink containing the first organic light-emitting material and applied above the first lower electrode to form the first organic light-emitting layer, the second ink containing the second organic light-emitting material and applied above the second lower electrode to form the second organic light-emitting layer, and the third ink containing the third organic light-emitting material and applied above the third lower electrode to form the third organic light-emitting layer, and the first column bank has a lower height than the second column bank. ### Claim 10 A display panel comprising: a substrate; a first lower electrode, a second lower electrode, and a third lower electrode that are disposed on the substrate and are spaced away from one another in a first direction; a first column bank disposed above the substrate and between the first lower electrode and the second lower electrode, and extending in a second direction intersecting the first direction; a second column bank disposed above the substrate and between the second lower electrode, and the third lower electrode and extending in the second direction; a first organic light-emitting layer disposed above the first lower electrode, a second organic light-emitting layer disposed above the second lower electrode, and a third organic light-emitting layer disposed above the third lower electrode; and an upper electrode disposed above the first organic light-emitting layer, the second organic light-emitting layer, the third organic light-emitting layer, the first column bank, and the second column bank, wherein the first organic light-emitting layer contains a first organic light-emitting material, the second organic light-emitting layer contains a second organic light-emitting material that has the same light-emission color as the first organic light-emitting material, the third organic light-emitting layer contains a third organic light-emitting material that has a light-emission color that is different from the first organic light-emitting material, ink-separating capability of the first column bank for separating a first ink and a second ink is lower than ink-separating capability of the second column bank for separating the second ink and a third ink, the first ink containing the first organic light-emitting material and applied above the first lower electrode to form the first organic light-emitting layer, the second ink containing the second organic light-emitting material and applied above the second lower electrode to form the second organic light-emitting layer, and the third ink containing the third organic light-emitting material and applied above the third lower electrode to form the third organic light-emitting layer, and liquid repellency of the first column bank against the first ink and the second ink is lower than liquid repellency of the second column bank against the second ink and the third ink. ### Claim 11 (depends on 9) The display panel of claim 9, wherein the first organic light-emitting layer and the second organic light-emitting layer each extend onto the first column bank and are in contact with each other. ### Claim 12 (depends on 9) The display panel of claim 9, wherein a thickness of the first organic light-emitting layer and a thickness of the second organic light-emitting layer are greater than a thickness of the third organic light-emitting layer. ### Claim 13 (depends on 9) The display panel of claim 9, wherein at least one of the first organic light-emitting layer, the second light-emitting layer, and the third organic light-emitting layer has a width in the first direction that differs from widths in the first direction of the rest of the first organic light-emitting layer, the second light-emitting layer, and the third organic light-emitting layer. ### Claim 14 (depends on 13) The display panel of claim 13, wherein an organic light-emitting layer that has the shortest luminance half-life among the first organic light-emitting layer, the second organic light-emitting layer, and the third organic light-emitting layer has the greatest width in the first direction among the first organic light-emitting layer, the second organic light-emitting layer, and the third organic light-emitting layer. ### Claim 15 (depends on 13) The display panel of claim 13, wherein an organic light-emitting layer that has the longest luminance half-life among the first organic light-emitting layer, the second organic light-emitting layer, and the third organic light-emitting layer has the smallest width in the first direction among the first organic light-emitting layer, the second organic light-emitting layer, and the third organic light-emitting layer.