Electrophoretic display device and method for manufacturing the same

Patent metadata

Field	Value
Publication number	US-9470949-B2
Application number	US-201314344834-A
Country	US
Kind code	B2
Filing date	May 2, 2013
Priority date	Feb 28, 2013
Publication date	Oct 18, 2016
Grant date	Oct 18, 2016

Abstract

Embodiments of the present invention relates to an electrophoretic display (EPD) device and a method for manufacturing the EPD device. The EPD device includes an electrophoretic substrate and a drive substrate arranged opposite to each other and a plurality of microcups disposed between the electrophoretic substrate and the drive substrate, each microcup includes a cup body for defining an accommodating space; a thickness of the cup body on one side of the microcup closer to the electrophoretic substrate is less than a thickness of the cup body on one side of the microcup closer to the drive substrate; and a cup surface of the microcup is a cambered surface which is away from a vertical central axis of the microcup and concave towards the cup body.

First claim

The invention claimed is:

1. An electrophoretic display (EPD) device, comprising an electrophoretic substrate and a drive substrate arranged opposite to each other and a plurality of microcups disposed between the electrophoretic substrate and the drive substrate,
wherein each microcup includes a cup body for defining an accommodating space; a thickness of the cup body on one side of the microcup closer to the electrophoretic substrate is less than a thickness of the cup body on one side of the microcup closer to the drive substrate; and a cup surface of the microcup is a cambered surface which is away from a vertical central axis of the microcup and concave towards the cup body, wherein
the cup body is formed by a plurality of partition walls arranged in an array; upper surfaces and lower surfaces of the partition walls are parallel to each other; and both the two side-walls of the partition wall are cambered surfaces, and
a height of the partition walls is ranged from 1 to 10 micrometers; and a radius of the cambered surface of the two side-walls of the partition walls is ranged from 4 to 10 micrometers.

2. The EPD device according to claim 1 , herein a shape of the cambered surface is one part of a spherical or ellipsoidal shape.

3. The EPD device according to claim 1 , wherein the partition walls are made of an opaque material; and an optical density of the opaque material is ranged from 1 to 5.

4. The EPD device according to claim 1 , wherein the drive substrate includes a thin-film transistor (TFT) of each sub-pixel and a data line and a scanning line which are intersected with each other; and the partition walls are disposed in regions corresponding to the data line and the scanning line.

5. A method for manufacturing an EPD, comprising the step of forming a microcup array on a drive substrate, wherein the microcup array is formed by a patterning process or pressing in by roll-to-roll method; each microcup includes a cup body for defining an accommodating space; a thickness of the cup body on one side of the microcup closer to the electrophoretic substrate is less than a thickness of the cup body on one side of the microcup closer to the drive substrate; and a cup surface of the microcup is a cambered surface which is away from a vertical central axis of the microcup and concave towards the cup body,
the cup body is formed by a plurality of partition walls arranged in an array; upper surfaces and lower surfaces of the partition walls are parallel to each other; and both the two side-walls of the partition wall are cambered surfaces, and
a height of the partition was is ranged from 1 to 10 micrometers; and a radius of cambered surface of the two side-walls of the partition walls is ranged from 4 to 10 micrometers.

6. The method according to claim 5 , wherein the step of forming the microcup array by a patterning process further comprises the following steps;
step S1): forming a microcup film layer and a photoresist layer on the drive substrate;
step S2): performing exposure on the photoresist layer;
step S3); performing development on the exposed photoresist layer;
step S4): performing isotropic etching on the microcup film layer; and
step S5): removing the photoresist to obtain the microcup array.

7. The method according to claim 6 , wherein before the step S5, the method further comprises: performing back exposure on the etched microcup film layer from one side of the drive substrate not provided with the microcups; and
correspondingly, after the step of removing the photoresist in the step S5, the method further comprises: performing thermocuring on the microcup film layer subjected to back exposure.

8. The method according to claim 5 , wherein convex roller gears of which a size and a shape are the same with those of the microcups are formed in a roll-to-roll device when the microcup array is formed in by roll-to-roll method.

Assignees

• Chengdu Boe Optoelect Tech Co
• Boe Technology Group Co Ltd

Inventors

• Chen Zhenxia
• Li Xiao
• Jiang ni

Classifications

• G02F1/0102

  Constructional details, not otherwise provided for in this subclass · CPC title

• G02F2001/1672

  Physics · mapped topic

• G02F1/167 Primary

  by electrophoresis · CPC title

• G02F1/1681

  having two or more microcells partitioned by walls, e.g. of microcup type · CPC title