KR20110032357A - Method of manufacturing flexible display device and flexible display device manufactured by the same method - Google Patents

Abstract

PURPOSE: A manufacturing method of a flexible displaying device and a flexible display element using an electrophoresis mode are provided to simplify a manufacturing process by eliminating top release paper and to manufacture a partition wall with a film. CONSTITUTION: A first substrate(1a) and a second substrate(1a') are included. A first electrode and a second electrode are included in the first substrate and the second substrate. A partition wall is formed between the first electrode and the second electrode. A first adhesive layer and a second adhesive layer are formed on both sides of a soft film. The partition wall is formed in a thin film. The partition wall is laminated on the first electrode by removing a first release paper.

Description

TECHNICAL FIELD OF THE INVENTION A flexible display device manufactured by the same, and a flexible display device manufactured by the same, and a flexible display device manufactured by the same.

The present invention relates to a method of manufacturing a flexible display device using an electrophoresis method and a flexible display device manufactured thereby.

The flexible display device is a display device capable of displaying characters or images by millions of particles scattered between flexible substrates such as thin plastics. The flexible display device can be applied to various fields such as newspapers, books, small displays, removable displays, and advertisement displays. Especially, the flexible display device can be used for display of electronic newspapers, e-books or electronic frames due to its advantage of being bent or rolled. Do.

In addition to the electrophoretic phenomena, a flexible display device can be implemented using liquid crystal, organic light emitting diodes (EL), reflective film reflective displays, twisted balls, and mechanical reflective displays. Most notable are flexible display devices using electrophoresis.

The flexible display device using the electrophoresis method is based on electrophoresis, which applies a magnetic field to a conductive material to make it move, and distributes conductive particles among the flexible substrates and then changes the polarity of the electromagnetic field. The data is represented by a change in the arrangement of charged particles. In this manner, when an image or text is displayed, there is an advantage of having bistability that can maintain frame data until a separate erasure is applied.

In order to commercialize the flexible display using the electrophoresis method, it is necessary to increase the uniformity and contrast ratio of the particles when driving the panel. To this end, it is important not only to develop good particles, but also to manufacture a panel that improves the mobility of particles and prevents aggregation between particles when the display device is driven. In order to manufacture panels for improving the uniformity, contrast ratio and mobility of particles, it is important to uniformly mix the charged particles and fill an appropriate amount in the area (unit cell) separated by the partition wall. It is important to join the bulkhead and the top and bottom plates so that they do not cross over to other unit cells. Particularly, when the flexible display device is bent or bent, the bonding method is very important because the partition wall is lifted up if the bonding is not performed well, and the particles may rise to the partition wall or move to another cell.

Regarding the joining of a partition and a board | substrate, the pasting method was proposed by various patent documents.

Korean Patent Laid-Open Publication No. 10-2006-0032111 discloses a method of bonding a partition wall and a substrate using a thermal fusion method after transferring an adhesive means to an upper portion of a transparent electrode, and Korean Patent Laid-Open Publication No. 10-2006-0067006 The method discloses a method of bonding to an ultraviolet lamp using an ultraviolet curing adhesive as an adhesive means. However, the above method is not preferable to increase the uniformity and contrast ratio of the filled particles because there is a possibility that the particles are immobilized in the adhesive layer because there is an adhesive means on the substrate rather than the partition wall.

In addition, the Republic of Korea Patent Publication No. 10-2006-0069750, in consideration of the fact that the particles are distributed in the upper part of the partition in the process of filling the particles to interfere with the coalescing, after filling the particles, the upper part of the partition using a roller Disclosed is a method for removing particles remaining in the. However, since a separate process of removing particles using a roller is added, it is not preferable in terms of simplification of the manufacturing process, and the use of the roller for a long period of time causes other problems to remove particles attached to the roller. .

In addition, Korean Patent No. 10-0667511 discloses a partition structure in which the area of the intersection point of the lattice is expanded to increase the adhesion area between the partition wall and the upper and lower plates. However, when the area of the intersection of the partition walls is increased, the display area of the flexible display is reduced, which is undesirable in terms of resolution.

In addition, Korean Patent Publication No. 10-2007-0041197 discloses a method of applying an adhesive layer only on an upper part of a partition by applying an EVA adhesive to a substrate on which a partition is formed by vacuum deposition. However, applying a desired amount of adhesive by vacuum deposition is difficult to control, and also to apply an adhesive layer only on the upper part of the partition wall is also difficult to control.

The present inventors can easily charge the charged particles, and while studying the method of firmly bonding the partition and the upper and lower plates so that the charged particles do not pass to other unit cells in the unit cell, In the process of manufacturing the partition wall with a film coated with an adhesive layer on both sides of the flexible film and the release paper is attached to the upper and lower portions of the adhesive layer, not only the filling of particles is easy but also the partition wall and the upper and lower plates are easily joined together, and the manufacturing process is also performed. The present invention has been completed by confirming that it can be simplified.

Disclosure of Invention An object of the present invention is to provide a method of manufacturing a flexible display device using an electrophoresis method and a flexible display device manufactured thereby, which can simplify the manufacturing process by manufacturing a partition wall from a thin film including an adhesive layer in advance.

In order to achieve the above object, in one aspect the present invention is a first substrate and a second substrate; First and second electrodes inscribed in the first and second substrates, respectively; And a partition wall formed between the first electrode and the second electrode, wherein the first adhesive layer and the second adhesive layer are formed on both sides of the flexible film, and the first adhesive layer and the second adhesive layer are formed on the first adhesive layer and the second adhesive layer. Attaching a first release paper and a second release paper to form a thin film, and then forming a partition on the thin film; Attaching a partition wall to the first electrode by removing the first release paper; Injecting electrophoretic particles into the space formed by the partition wall; And removing the second release paper and attaching the partition wall to the second electrode to provide the method of manufacturing the flexible display device.

In the flexible display device, an insulating layer may be further formed between the first electrode or the second electrode and the partition wall.

The basic structure of the flexible display device manufactured by the above method is shown in FIG. 1, and includes a first substrate 1a and a second substrate 1a '; A first electrode (1b) and a second electrode (lb ') inscribed in the first substrate and the second substrate, respectively; And partition walls lc, 1c ', and ld formed between the first electrode and the second electrode. In particular, the partition wall has a structure in which the first adhesive layer 1c and the second adhesive layer 1c 'are coated on both surfaces of the flexible film ld.

The term "substrate" used in the present invention is located at the outermost part of the flexible display device to maintain the shape, and is not limited as long as the substrate can maintain the shape. Preferably, polyethylene terephthalate (PET); Polyethylene naphthalate (PEN), polycarbonate (PC), polyethersulfone (PES), colorless polyimide, AryLite, cycloolefin copolymer (COC), etc. It can be used as a substrate.

The term "electrode" as used in the present invention is for applying a voltage to a filled particle to display data. As shown in FIG. 1, when a voltage capable of moving the packed particles is applied to the first electrode 1a and the second electrode 1a ', the particles charged with black 1f and white 1e according to their polarities. Are attracted to the first electrode or the second electrode. When a negative voltage is applied to the second electrode and a positive voltage is applied to the first electrode, the positively charged white charged particles 1e move toward the second substrate and are negatively charged. The charged black charge 1f moves in the direction of the first substrate. Therefore, black and white control of each cell is possible according to the polarity of the electric field, and gray scale control of the pixel is also possible according to the amplitude of the electric field or the width of the pulse. As the electrode, any one having a transparent property may be used without limitation, an electrode commonly used in the art, and preferably, ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), or FTO (Fluorine-doped Tin). Oxide), IGZO (Indium Gallium Zinc Oxide), carbon nanotube (CNT) and the like can be used.

As used herein, the term "partition wall" refers to a frame for dividing a space filled with particles into a predetermined size. That is, the predetermined space in which the particles are filled in the partition wall means a pixel representing data of the flexible display device.

The term "flexible film" used in the present invention is not limited as long as it is a film that can be used by bending or rolling as a component of a partition of a flexible display device, and may be polycarbonate (PC) or polyethylene terephthalate (PET). , Polyether sulfone (PES), polyimide (PI) and the like can be used.

The term "adhesive layer" used in the present invention is a means for adhering the flexible film, the first electrode and the second electrode, and in view of adhering the partition wall of the manufactured flexible display device so as not to lift, ethylene vinyl acetate; EVA) copolymer films and the like can be used.

The term "release paper" used in the present invention is to be removed just before bonding the prepared partition wall to the first electrode and the second electrode, and serves to protect the adhesive layer until it is removed. The release paper may be used a release paper commonly used in the art, preferably a fluorinated polyethylene terephthalate (fluorinated PET) film and the like can be used.

The forming of the partition wall may include forming a first adhesive layer and a second adhesive layer on both sides of the flexible film, and attaching a first release paper and a second release paper on the first adhesive layer and the second adhesive layer, respectively, to form a thin film. Forming a partition on the thin film. In the manufactured thin film, a frame of a partition wall may be manufactured by using a pressing process or laser cutting. The partition wall manufactured by the above method is shown in FIG. 2.

When the partition wall is manufactured by the above steps, it is not necessary to apply the adhesive layer to the substrate or the partition wall by a separate process, and the problem of controlling the coating amount and the application position generated when the adhesive layer is applied only to the upper or lower portion of the manufactured partition wall. Can be eliminated to simplify the manufacturing process. In addition, because the release paper is attached to protect the adhesive layer can maximize the adhesive strength.

The partition wall may be manufactured in various forms according to the application of the flexible display device, and representative examples thereof are illustrated in FIGS. 3 and 4. As shown in Fig. 3, it is desirable to reduce the width 3a of the partition wall from several μm to several tens of μm in consideration of the resolution, and the width 3b of the pixel is also considered important.

The bonding of the partition wall to the first electrode by removing the first release paper may maximize the adhesive force by removing the release paper protecting the adhesive layer immediately before the bonding. In addition, since the adhesive layer already exists in the partition wall, it is not necessary to apply the adhesive layer to the electrode or the partition wall separately, thereby simplifying the process.

In addition, after the partition wall from which the release paper is removed is placed on the first electrode, the partition wall may be bonded by a roll-to-roll method using a roll press. In this case, even when using a roll presser, the second adhesive layer may be protected by the second release paper attached to the upper part of the partition wall, thereby simplifying the bonding process.

In the step of injecting electrophoretic particles into the partition wall, since the release paper attached to the upper part of the partition wall to protect the adhesive layer, it is possible to prevent some particles from adhering to the adhesive layer during the particle injection process.

Removing the second release paper and bonding the partition wall to the second electrode may be bonded in the same manner as removing the first release paper and attaching the partition wall to the first electrode. Particularly, after the particles are filled, a part of the particles remain on the upper part of the partition wall, and the particles remaining on the upper part of the partition wall may be removed together in the process of removing the release paper for bonding to the second electrode. Therefore, since a separate process of removing particles remaining on the upper part of the partition is not necessary, the manufacturing process can be simplified.

In another aspect, the present invention provides a flexible display device manufactured by the above method. The flexible display device of the present invention includes a first substrate and a second substrate; First and second electrodes inscribed in the first and second substrates, respectively; And a partition wall formed between the first electrode and the second electrode, and particularly, the partition wall is not lifted even when the flexible display device is rolled or bent in accordance with the method of the present invention.

According to the exemplary embodiment of the present invention, the partition wall may include a first adhesive layer and a second adhesive layer formed on both sides of the flexible film, and an insulating layer may be further formed between the first electrode or the second electrode and the partition wall. It may be. In this case, although the insulating layer is omitted, there is no problem in driving the flexible display device, but an insulating layer may be used to prevent a short between the upper electrode and the lower electrode. As the material of the insulating layer, any material that can be used as an insulating material may be used without limitation.

The method of manufacturing the flexible display device according to the present invention has the following effects.

First, in order to bond the partition wall to the substrate, an adhesive layer is absolutely necessary, and it is important that the adhesive layer is positioned only at the contact portion between the partition wall and the substrate, and that the adhesive layer does not exist in the remaining part. By manufacturing the partition wall, the adhesive layer may be positioned only at the portion to be bonded, thereby simplifying the manufacturing process.

Second, it is preferable to use a rule-to-roll method when bonding the partition wall to the substrate. In the present invention, since the release paper protects the adhesive layer, the other adhesive layer is protected by the release paper while one adhesive layer is bonded to the substrate. Even if the roll-to-roll method is used, the adhesive layer is not damaged, thereby simplifying the manufacturing process.

Third, in the process of filling the electrophoretic particles in the partition wall, some particles remain on the upper part of the partition wall, and the coalescence of the partition wall and the upper substrate may be prevented by these particles. This requires a process for removing the residual particles on the upper part of the partition, in the present invention, since the particles are filled in the state where the release paper is attached to the upper part of the partition, the remaining particles remain on the upper release paper, and thus can be easily removed by removing the upper release paper. Therefore, it is possible to simplify the manufacturing process while increasing the adhesive strength.

Hereinafter, preferred embodiments of the present invention will be presented to assist in understanding the present invention. However, the following examples are merely provided to more easily understand the present invention, and the contents of the present invention are not limited by the examples.

Example 1 Preparation of Bulkhead

In this embodiment, a polyethylene terephthalate (PET) film is used as a flexible film, an adhesive layer is formed of ethylene vinyl acetate (EVA) copolymer, and a fluorinated polyethylene terephthalate (fluorinated polyethylene terephthalate) is formed. fluorinated PET film was used as a release paper to form a partition.

First, both surfaces of the EVA copolymer were coated to form a first adhesive layer and a second adhesive layer, and then a first release paper and a second release paper were attached to both sides of the adhesive layer to prepare a thin film to be used as a partition wall. The barrier rib was manufactured so that the pattern of the barrier rib was in the form shown in FIG.

Example 2 Fabrication of Flexible Display Device

The first release paper of the partition wall manufactured in Example 1 was removed, and the first electrode was bonded to the patterned first substrate. At the time of bonding, the second release paper was not removed so that only the first adhesive layer could be attached to the first substrate, and was bonded using a roll press.

Electrophoretic particles are evenly packed in the pixels after the barrier ribs are attached to the first electrode, and when the amount of particles is too high or too low, the uniformity or visibility of the flexible display device is degraded. Filled uniformly.

After filling the particles, the second release paper attached to the upper part of the partition wall was removed, and then bonded to the electrode patterned second substrate, thereby manufacturing a flexible display device.

1 is a schematic cross-sectional view of an electrophoretic flexible display device according to an exemplary embodiment of the present invention.

2 is a schematic cross-sectional view of a partition for fabricating an electrophoretic flexible display device according to an exemplary embodiment of the present invention.

3 is a panel structure diagram of an electrophoretic flexible display device according to an exemplary embodiment of the present invention.

4 is a plan view illustrating various forms of an electrophoretic flexible display device partition wall according to an exemplary embodiment.

5 is an overall process diagram for manufacturing an electrophoretic flexible display device according to an embodiment of the present invention.

<Short description of the symbols in the drawings>

(1a): First substrate 1a ': Second substrate

(1b): First electrode 1b ': Second electrode

(1c): 1st contact bonding layer (1c '): 2nd contact bonding layer

(1d): flexible film (1e): charged particles (white)

(1f): charged particles (black)

(2a): first release paper (2a '): second release paper

(3a): width of partition wall (3b): width of pixel

Claims (14)

A first substrate and a second substrate; First and second electrodes inscribed in the first and second substrates, respectively; And a partition wall formed between the first electrode and the second electrode. Forming a thin film by forming a first adhesive layer and a second adhesive layer on both sides of the flexible film, attaching a first release paper and a second release paper on the first adhesive layer and the second adhesive layer, respectively, and then forming a partition on the thin film ; Attaching a partition wall to the first electrode by removing the first release paper; Injecting electrophoretic particles into the space formed by the partition wall; And And removing the second release paper and bonding the partition wall to the second electrode. The method of claim 1, wherein the flexible display device further comprises an insulating layer between the first electrode or the second electrode and the partition wall. The method of claim 1, wherein the first substrate or the second substrate is polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), polyethersulfone (polyethersulfone; PES), colorless transparent polyimide (Colorless polyimide), AryLite, and a method of manufacturing a flexible display device characterized in that it is formed of a material selected from the group consisting of cycloolefin copolymers (COC). The method of claim 1, wherein the first electrode or the second electrode is Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), Fluorine-doped Tin Oxide (FTO), Indium Gallium Zinc Oxide (IGZO), and Carbon Nanotubes (carbon nano tube; CNT) A method of manufacturing a flexible display device, characterized in that formed of a material selected from the group consisting of. The method of claim 1, wherein the flexible film is made of polycarbonate (PC), polyethylene terephthalate (PET), polyether sulfone (PES), and polyimide (PI). A method of manufacturing a flexible display device, characterized in that formed of a selected material. The method of claim 1, wherein the adhesive layer is formed of an ethylene vinyl acetate (EVA) copolymer. The method of claim 1, wherein the release paper is a fluorinated polyethylene terephthalate (fluorinated PET) film. The method of claim 1, wherein the forming of the barrier rib on the thin film is performed by a pressing process or a laser cutting process. The method of claim 1, wherein the attaching the partition wall to the first electrode or the attaching the partition wall to the second electrode is performed using a roll presser. The method of manufacturing a flexible display device according to claim 1, wherein the partition wall has a circular shape, a square shape, an equilateral triangle shape, or a regular hexagon shape when viewed from above. A flexible display device manufactured according to any one of claims 1 to 10. The display device of claim 11, wherein the flexible display device comprises: a first substrate and a second substrate; First and second electrodes inscribed in the first and second substrates, respectively; And a partition wall formed between the first electrode and the second electrode. The flexible display device of claim 12, wherein the barrier rib comprises a first adhesive layer and a second adhesive layer formed on both sides of the flexible film. The flexible display device of claim 12, wherein the flexible display device further comprises an insulating layer between the first electrode or the second electrode and the partition wall.

Images