# US 11,309,509 B2 · Display device and manufacturing method for same

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,309,509 B2
- Document ID: US11309509B2
- Status: Granted
- Kind: B2
- Application number: 16/981,480
- Filed: 2018-03-22
- Published: 2021-02-04
- Granted: 2022-04-19
- Earliest claimed: 2018-03-22
- Assignees: Sharp Kabushiki Kaisha
- Applicants: Sharp Kabushiki Kaisha
- Inventors: Yasushi Asaoka; Shigeru Aomori
- Web page: https://patentgrep.com/patent/US11309509B2

## CPC

- H10K 71/135: {using ink-jet printing}
- H05B 33/14: characterised by the chemical or physical composition or the arrangement of the electroluminescent material {, or by the simultaneous addition of the electroluminescent material in or onto the light source}
- H10K 50/115: comprising active inorganic nanostructures, e.g. luminescent quantum dots
- H10K 59/80518: {Reflective anodes, e.g. ITO combined with thick metallic layers}
- H10K 59/80524: {Transparent cathodes, e.g. comprising thin metal layers}
- H10K 59/8731: {multilayered coatings having a repetitive structure, e.g. having multiple organic-inorganic bilayers}
- H10K 71/80: using temporary substrates
- H10K 71/851: {Division of substrate}
- H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES
- H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL

## Abstract

A display device is provided with a light-emitting element layer including an anode electrode, a cathode electrode, and a quantum dot light-emitting layer sandwiched between the anode electrode and the cathode electrode, wherein the quantum dot light-emitting layer includes at least quantum dots and nanofibers. A method for manufacturing a display device includes forming a quantum dot light-emitting layer by applying a colloidal solution including at least quantum dots and nanofibers by ink-jet.

## Claims

### Claim 1

A display device, comprising:
a light-emitting element including
an anode electrode,
a cathode electrode, and
a quantum dot light-emitting layer sandwiched between the anode electrode and the cathode electrode,
wherein the quantum dot light-emitting layer includes at least quantum dots and nanofibers.

### Claim 2 (depends on 1)

The display device according to claim 1,
wherein a number of the quantum dots included in the quantum dot light-emitting layer is greater than a number of the nanofibers.

### Claim 3 (depends on 1)

The display device according to claim 1,
wherein a diameter of the nanofibers included in the quantum dot light-emitting layer is less than a diameter of the quantum dots, and
a length of the nanofibers is greater than the diameter of the quantum dots.

### Claim 4 (depends on 1)

The display device according to claim 1,
wherein a length of the nanofibers included in the quantum dot light-emitting layer ranges from not less than 2 times a thickness of the quantum dot light-emitting layer to not greater than 1 μm.

### Claim 5 (depends on 1)

The display device according to claim 1,
wherein the light-emitting element further comprises a charge transport layer and a hole transport layer, and
the charge transport layer and/or the hole transport layer include nanofibers.

### Claim 6 (depends on 1)

The display device according to claim 1,
wherein the nanofibers are cellulose nanofibers.

### Claim 7 (depends on 1)

The display device according to claim 1,
wherein the nanofibers are TEMPO-oxidized cellulose nanofibers.

### Claim 8

A method for manufacturing a display device, comprising:
forming a quantum dot light-emitting layer by applying a colloidal solution including at least quantum dots and nanofibers by ink-jet.

### Claim 9 (depends on 8)

The method for manufacturing a display device according to claim 8,
wherein an amount of nanofibers in the colloidal solution is greater than 0 and less than or equal to 1 wt. %.

### Claim 10 (depends on 8)

The method for manufacturing a display device according to claim 8,
wherein a viscosity of the colloidal solution at room temperature (from 20° C. to 25° C.) ranges from 5 mPa·s to 20 mPa·s.