JP7272720B1 - Cover plate having foldable area for covering display module, manufacturing method thereof, display panel and display device using same - Google Patents

Abstract

An object of the present invention is to realize bending performance of a cover body by forming a concave portion in a foldable region of the cover body, and to form a concavo-convex structure on the upper surface of the cover body so that the concave portion can be bent. Disclosed is a cover plate with a foldable area for covering a display module, a method for manufacturing the same, a display panel and a display device having the cover plate, which can reduce visibility problems. A cover body constituting a cover plate has a first surface and a second surface, the second surface has at least one concave portion formed in a bendable region, and the first surface has a bendable region. At least one first uneven structure is formed in the possible area. [Selection drawing] Fig. 1

Description

TECHNICAL FIELD The present invention relates to the technical field of display devices, and more particularly to a cover plate with foldable regions for covering display modules, a method for manufacturing the same, a display panel and a display device.

With the continuous development of flexible OLED technology, flexible OLED displays mounted on mobile phone terminals, other communication terminals and tablet terminals have become more and more widely used.
In addition, mobile phone terminals, other communication terminals, and tablet terminals are diversifying from SF (fixed curvature) to DF (foldable), and technological development of foldable products is progressing more and more.

For example, Patent Literature 1 discloses an invention relating to a display module that uses a flexible screen and has a high percentage of visible area.
According to the invention, the front surface provided with the flexible screen can be recessed with a constant curvature and can be concave or convex.

However, foldable products use cover plates made of transparent and flexible materials such as Colorless Polyimide (CPI). Since the display is on the surface of the main body of the product, if the display collides with a hard object when dropped, a phenomenon called dot dropout will occur, and there are problems such as display abnormalities such as the GDS phenomenon and damage.

Moreover, Patent Document 1 does not disclose any means for eliminating the parallax caused by the step in the bendable area.

JP 2019-070829 A

Therefore, in view of the above problems, the present invention provides a cover plate having a foldable area for covering a display module that satisfies the rigidity and bending performance of the cover plate and eliminates the parallax caused by the step of the foldable area. , a manufacturing method thereof, a display panel, and a display device.

To solve the problems in the prior art, the present invention takes the following technical solutions.
In the description of the present invention, terms indicating directions and positional relationships such as "inner", "lower", and "upper" are based on the directions shown in the drawings, directions frequently placed during work, and positional relationships. .
Also, any orientation or positional relationship is for the purpose of describing the invention and simplifying the description, and the referenced device or element must have a particular orientation and be constructed or operated in a particular orientation. It is not intended to indicate or imply
Further, terms such as "first,""second," etc. are used only to distinguish between the descriptions and are not meant to indicate or imply any relative importance.

A cover plate having foldable regions according to the present invention comprises:
A cover plate having a foldable area for covering a display module, comprising:
The cover plate consists of a cover body made of various ultra-thin glass materials having a first surface and a second surface,
The first surface has a first uneven structure consisting of a plurality of fine unevenness in a bendable region,
the second surface has at least one recess formed in the foldable region;
A second uneven structure is formed on the surface of the recess,
In the second concave-convex structure, a plurality of fine concave-convex structures are formed sparsely in the central portion of the concave portion and densely on both side portions of the concave portion.
It is characterized by

A cover plate having foldable regions according to the present invention comprises:
In addition to the above features,
The second surface is formed with at least three film layers,
The refractive index of the film layer is alternately set between a low refractive index and a high refractive index in the direction from the first surface to the second surface.
It is characterized by

A cover plate having foldable regions according to the present invention comprises:
In addition to the above features,
The three film layers on the second side are
A first film layer, a second film layer, and a third film layer having different refractive indices are laminated,
The refractive index of the first film layer is substantially the same as the refractive index of the cover body,
the refractive index of the second film layer is greater than the refractive index of the first film layer;
the refractive index of the second film layer is greater than the refractive index of the third film layer;
It is characterized by

A cover plate having foldable regions according to the present invention comprises:
In addition to the above features,
The first film layer is
It is characterized by covering the concave portion formed on the second surface while being in contact with the second surface.

A cover plate having foldable regions according to the present invention comprises:
In addition to the above features,
The first uneven structure is
Randomly formed on the first surface, the size of the plurality of fine uneven recesses of the first uneven structure is 0.1 to 2 μm.
A cover plate with foldable regions according to claim 1, characterized in that:

A method of manufacturing a cover plate having a bendable region as described above, comprising:
a step of fixing and mounting the cover body;
forming at least one recess in the bendable area of the second surface of the cover body;
a step of forming a rough-processed second uneven structure on the surface of the recess;
so that the distribution density of the recesses of the second uneven structure gradually increases from the center of the recess toward both ends,
In the rough processed second uneven structure,
In the center of the recess , the moving speed of the spray gun that sprays the etchant is increased to form unevenness with a small distribution density,
a step of slowing down the moving speed of the spray gun for spraying the etchant on both sides of the recess to form unevenness with a high distribution density;
forming a first concave-convex structure in the foldable region of the first surface;
characterized by comprising

The display panel according to the present invention is
a display module;
a cover plate having the bendable region;
characterized by comprising

A display device according to the present invention includes:
It is characterized by comprising the display panel described above.

In the bendable cover plate according to the present invention, the concave portion is formed in the bendable region of the cover body to realize the bending performance of the cover body, and the concave-convex structure is formed on the upper surface of the cover body, It is possible to reduce visibility problems caused by recesses, improve the display performance of the panel, and improve user satisfaction.

FIG. 2 is an end view of a cut portion showing a cross-sectional structure of a display cover plate having foldable regions; Explanatory diagram showing the principle of light refraction and reflection Explanatory drawing schematically showing directions of refraction and reflection of light incident on a display cover plate having a foldable region. FIG. 2 is an end view of a cut portion showing a cross-sectional structure of a display cover plate having a bendable region in which an organic coating layer is formed on the upper surface of the bendable region of Example 1; FIG. 2 is a flow chart showing the manufacturing procedure of the display cover plate having bendable regions of Example 1. FIG. An end view of a cut portion showing a cross-sectional structure of a display cover plate having a bendable region of Example 2. FIG. 10 is a flow diagram showing the manufacturing procedure of the display cover plate having a bendable region of Example 2; FIG. 10 is a flow diagram showing a procedure for forming recesses and a second concave-convex structure in a display cover plate having a foldable region according to Embodiment 2; An end view of a cut portion showing a cross-sectional structure of a display cover plate having a foldable region of Example 3. Explanatory diagram schematically showing the difference in the refractive index of light due to film layers FIG. 10 is a flow diagram showing the manufacturing procedure of the display cover plate having a foldable region of Example 3; FIG. 2 is a schematic diagram showing an embodiment of a sputtering apparatus used to form a first film layer on a display cover plate having foldable regions; An end view of a cut portion showing a cross-sectional structure of a display cover plate having a foldable region of Example 4. FIG. 10 is a flow chart showing the manufacturing procedure of the display cover plate having foldable regions of Example 4;

Specific embodiments of the present invention will be described in detail with reference to the drawings.

A cover plate with a foldable area covering the display module consists of a cover body 10 having a first side 101 and a second side 102, as shown in FIG.
The second surface 102 has at least one recess 20 formed in the bendable area.
The first surface 101 has a first concave-convex structure 50 formed in a bendable region.

The "first surface 101" and the "upper surface" of the cover body 10 refer to the surface farther from the display module when the cover plate is attached to the display module.
The "second surface 102" and the "lower surface" of the cover body 10 refer to surfaces closer to the display module when the cover plate is attached to the display module.
That is, "top" refers to the side farther from the display module, and "bottom" refers to the side closer to the display module.

The present invention designs the cover plate with unequal thickness and forms recesses 20 in the bendable area to prevent the phenomenon called dot dropout in the non-bendable area and ensure the mechanical properties of the display module. while securing the flexibility of the bendable region.

However, by forming the concave portion 20 in the cover plate, a parallax occurs due to the difference in thickness (step) from the peripheral portion of the concave portion 20, and the image appears to be distorted.
It is considered that this is because the angle of refraction of light differs between the concave portion 20 and its peripheral portion.

According to the law of refraction, when light propagates through two media, for example, as shown in FIG. and the second interface Y, the reflected light d1' and the refracted light d2 are separated.

Here, the angles between θ1 and θ1′ are the same, and when light is directed from a light-poor medium to a light-dense medium, the angle θ2 will be less than the angle θ1 and vice versa.
Therefore, in the present invention, the parallax problem is solved by forming the first uneven structure 50 on the first surface 101 .
Specifically, the light that has entered the cover plate through the recesses 20 on the second surface 102 passes through the cover plate as it is, and enters the first uneven structure 50 on the first surface 101. Reflection occurs simultaneously with refraction at the surface.

At this time, part of the refracted light is radiated from the upper surface side. The light emitted from the structure 50 is uniform and the light passing inside the cover plate appears to be emitted from the first surface 101 in a straight line.

The detailed principle is as shown in FIG. The reflected light is radiated from the upper surface side, and the reflected light is irradiated to another uneven portion forming the first uneven structure 50 to repeat reflection and refraction, and the further refracted light is irradiated to another uneven portion. This causes repeated refraction and reflection.
As a result, a diffuse reflection effect is obtained, and uniform light is radiated from the first concave-convex structure 50 .

<Example 1>
A cover plate with a foldable area covering the display module consists of a cover body 10 having a first side 101 and a second side 102, as shown in FIG.
For the cover body 10, various flexible ultrathin glass materials such as quartz glass, high silica glass, soda lime glass, aluminosilicate glass, boric acid glass, phosphate glass, or borosilicate glass can be used.

The second surface 102 has at least one recess 20 formed in the bendable area.
The first surface 101 has a first concave-convex structure 50 formed in a bendable region.
The first concave-convex structure 50 is randomly formed on the first surface 101, and the size of the plurality of fine concave-convex structures of the first concave-convex structure 50 is 0.1 to 2 μm.
In the first uneven structure 50, a plurality of fine unevenness is formed, and in addition to irregular unevenness, regular unevenness can be formed, and the unevenness itself can be distributed irregularly or regularly. can also
The shape of the unevenness is a geometric shape, and examples thereof include rectangles, triangles, circles, ellipses, and the like.

When the cover body 10 is made of a glass material, the method of forming the first concave-convex structure 50 can form irregular concave-convex structures by etching, for example.
In the etching method, an etchant containing an acidic compound is used.
Since the main chemical composition of the cover body 10 is SiO ₂ , SiO ₂ reacts with acidic compounds to form silicate, which adheres to the surface of the cover body 10 .
Since the acidic compound corrodes only the surface of the cover body 10, the surface of the cover body 10 is uneven.

In this embodiment, in addition to forming a first concave-convex structure 50 having a certain degree of roughness in the bendable region of the upper surface (first surface 101) of the cover body 10, the first surface 101 of the cover body 10 is made of a polymer material. An organic coating layer 40 is formed.
The organic coating layer 40 can reduce the surface roughness of the upper surface of the cover body 10 (first surface 101).
In addition, the organic coating layer 40 can improve mechanical properties such as elastic modulus, bending resistance, and tensile resistance of the cover plate, improve the appearance, and improve the feeling of use.

The size of the first concave-convex structure 50 is not limited.
The shape of the recess 20 is not limited, and the cross section can be rectangular, triangular, or arc-shaped.
The recess depth of the recess 20 can be arbitrarily selected, and can be determined, for example, according to the bending radius of the bendable region.
The refractive index of the organic coating layer 40 is approximately the same as the refractive index of the cover body 10 .
By using UTG (Ultra Thin Glass) with high elastic modulus and hardness for the cover body 10 and forming the organic coating layer 40 on the upper surface (first surface 101) of the cover body 10, the mechanical properties are improved and the cost is reduced. It also solves the parallax problem.

A cover plate with foldable regions covering the display module can be manufactured by the following procedure, as shown in FIG.

(S11)
The cover body 10 is fixed and attached to the processing apparatus.
The cover body 10 is preferably made of glass.

(S12)
At least one recess 20 is formed in the bendable area of the second surface 102 of the cover body 10 .
Means for forming the recesses 20 include, but are not limited to, mechanical cutting, etching, and the like.

(S13)
A first concave-convex structure 50 is formed in the bendable region of the first surface 101 of the cover body 10 .
The means for forming the first concave-convex structure 50 is preferably etching, but is not limited to this.
In the step of forming the first concave-convex structure 50, an ink protective layer is formed on the non-etching regions, and the ink protective layer is removed after the etching is completed.
The ink protection layer can protect the ink protection areas and prevent the etchant from affecting the non-etching areas.
The material for the ink protective layer can be selected from conventional photocurable inks, thermosetting inks, and the like.
In this embodiment, the ink material and ink removal method are not limited, and can be freely selected as long as the cover body 10 is not damaged.

(S14)
An organic coating layer 40 is formed on the first surface 101 .
Methods for forming the organic coating layer 40 include, but are not limited to, a coating method, a vapor deposition method, and the like.
The organic coating layer 40 means a thin film produced by depositing or coating an organic coating material on the cover body 10 .

The ink protective layer, organic coating layer 40, can be deposited and coated by any method.
Vapor deposition can be selected from, for example, one or more of sputtering, vapor deposition, chemical vapor deposition, etc., and coating can be selected, for example, from one or more of spray coating, spin coating, and the like.

Since the first concave-convex structure 50 is located on the upper surface (first surface 101) of the cover body 10, if the concave-convex shape is too large, it is easy to feel rough and uncomfortable to use, and there is a possibility that defects may occur during the manufacturing process. Therefore, it is preferable that the surface has a fine irregular shape with blunt corners, such as a round grain structure with a smooth surface.

The etchant for forming the first concave-convex structure 50 contains 2-15 wt % hydrofluoric acid, 0.3-4 wt % ammonium fluoride, 2-15 wt % inorganic acid, and water.
Hydrofluoric acid in the etching solution contains very strong electrophilic particles H+ and moderately electrophilic particles F-, and has a strong ability to decompose glass. It forms a silicate and is easily dissolved in the etchant.

Ammonium fluoride is alkaline, forms a buffer solution together with hydrofluoric acid, adjusts the etching rate, controls the shape of fine irregularities, and avoids excessive etching.
Inorganic acids provide H+ to adjust the etching rate, and act synergistically with hydrofluoric acid and ammonium fluoride to produce fine irregularities with blunt corners, such as smooth-surfaced round grain structures. Make it easier to form.

It was experimentally confirmed that the formation of the first concave-convex structure 50 layer with an etchant significantly improves the dynamic bending properties of the glass and greatly increases the bending radius that resists breakage, that is, improves the bending strength.
The etchant can form unevenness of 0.1 to 2 μm on the surface (first surface 101) of the cover body .

<Example 2>
The cover plate with foldable regions according to this embodiment comprises a cover body 10, as shown in FIG.
The second surface 102 of the cover body 10 is formed with at least one recess 20 in the bendable area.
On the first surface 101 of the cover body 10, a first uneven structure 50 is formed in a foldable region.
A second concave-convex structure 60 is formed on the surface of the concave portion 20 .
The distribution density of the recesses in the second uneven structure 60 gradually increases from the central portion of the recesses 20 toward both ends.

Since the central portion of the concave portion 20 is formed with coarse unevenness and the both end portions are formed with fine unevenness, the refraction effect is enhanced, and the light incident on the concave portion 20 and passing through the cover body 10 is refracted or reflected. The direction can be made uniform (variation can be suppressed).

The second uneven structure 60 is formed with a plurality of fine unevenness, and in addition to irregular unevenness, regular unevenness can be formed, and the unevenness itself can be distributed irregularly or regularly. can also
The shape of the unevenness is a geometric shape, and examples thereof include rectangles, triangles, circles, ellipses, and the like.
As for the method of forming the second uneven structure 60, when the cover body 10 is made of a glass material, it is possible to form irregular unevenness by etching, for example.

In the etching method, an etchant containing an acidic compound is used.
Since the main chemical composition of the cover body 10 is SiO ₂ , SiO ₂ reacts with acidic compounds to form silicate, which adheres to the surface of the cover body 10 .
Since the acidic compound corrodes only the surface of the cover body 10, the surface of the cover body 10 is uneven.

In this embodiment, in addition to forming a second concave-convex structure 60 having a certain roughness in the foldable region of the lower surface (second surface 102) of the cover body 10, the first surface 101 of the cover body 10 is coated with a polymer A film layer 30 of material is formed.
The film layer 30 can reduce the surface roughness of the upper surface of the cover body 10 (first surface 101).
In addition, the film layer 30 can improve mechanical properties such as elastic modulus, bending resistance, and stretch resistance of the cover plate, reduce surface roughness, improve appearance, and improve usability. .

The refractive index of the film layer 30 formed on the upper surface (first surface 101) of the cover body 10 is substantially the same as that of the cover body 10, which improves mechanical properties, reduces costs, and eliminates the problem of parallax. Solvable.
A cover plate with foldable regions covering the display module can be manufactured by the following procedure, as shown in FIG.

(S21)
The cover body 10 is fixed and attached to the processing apparatus.
The cover body 10 is preferably made of glass.

(S22)
At least one recess 20 is formed in the bendable area of the second surface 102 of the cover body 10 .
Means for forming the recesses 20 can be selected from mechanical cutting or chemical etching.

(S23)
A second uneven structure 60 is formed on the surface of the recess 20 .
The means of forming the second relief structure 60 is preferably performed by chemical etching.
For example, the concave portion 20 is formed in the cover body 10 by molding such as laser processing or etching, and then the second uneven structure 60 is formed on the surface of the concave portion 20 by etching.
By making the process of forming the second concave-convex structure 60 the same process as the process of forming the recesses 20, it is possible to optimize the processing procedure and improve the efficiency by simultaneous processing.

Since the formation of the second ruggedness structure 60 requires an irregular distribution of ruggedness, as shown in FIG. forming structure 60;

(S201)
In the etching process for forming the recesses 20, the etching speed and etching time are controlled, the spray gun is moved at a constant speed, and the recesses 20 with a constant depth are formed.
Preferred conditions for the step of spraying the etching solution onto the cover body 10 are an etching solution temperature of 25 to 30° C., a spray pressure of 0.1 to 0.8 Pa, a spray flow rate of 10 to 15 sccm, and a spray time of 5 to 10 minutes.
The indoor temperature is set at 20-22 degrees.

(S202)
The surface of the recess 20 is roughened to form unevenness with a low density in the central portion of the surface of the recess 20 .
In the etching process, the etchant is sprayed, and in the central portion, a small amount of the etchant is sprayed at a low density.
Preferable conditions for the etching step are an etchant temperature of 25 to 30° C., a spray pressure of 0.1 to 0.8 Pa, a spray flow rate of 10 to 15 sccm, and a spray time of 3 to 8 minutes.
In this process, the spray gun is moved at a constant speed to spray the etchant.

(S203)
The surface of the recess 20 is deeply processed to form finer unevenness on both ends of the surface of the recess 20 .
In the etching process, an etchant is sprayed, and at both ends, a large amount of the etchant is sprayed at a high density.
Preferable conditions for the etching step are an etching solution temperature of 25 to 30° C., a spray pressure of 1 to 1.5 Pa, a spray flow rate of 25 to 30 sccm, and a spray time of 3 to 5 minutes.
Thus, in the etching steps of S202 and S203, the spray gun is moved quickly in the central portion of the surface of the recess 20 and moved slowly at both ends.

That is, first, the recesses 20 are formed at a high temperature, pressure and flow rate at high speed, and then the second relief structure 60 is rough-processed at a low temperature, pressure and flow rate.
Finally, in the roughly processed second uneven structure 60, the central portion of the concave portion 20 is controlled to move quickly to complete unevenness with a small distribution density, and the both sides of the concave portion 20 are controlled to move slowly to achieve a distributed density. Complete the large unevenness of

(S24)
A first concave-convex structure 50 is formed in the bendable area of the first surface 101 of the cover plate.
A means for forming the first concave-convex structure 50 is etching.
In the step of forming the first concave-convex structure 50, an ink protective layer is formed on the non-etching regions, and the ink protective layer is removed after the etching is completed.
The ink protection layer can protect the ink protection areas and prevent the etchant from affecting the non-etching areas.
The material for the ink protective layer can be selected from conventional photocurable inks, thermosetting inks, and the like.
In this embodiment, the ink material and ink removal method are not limited, and can be freely selected as long as the cover body 10 is not damaged.

(S25)
A first film layer 301 is formed on the first surface 101 .
Means for forming the first film layer 301 include, but are not limited to, coating or vapor deposition.
The film layer 30 means a thin film produced by vapor-depositing or coating an organic material or inorganic material on the cover body 10 .
The first film layer 301, film layer 30 can be deposited and coated by any method.
Vapor deposition can be selected from, for example, one or more of sputtering, vapor deposition, chemical vapor deposition, etc., and coating can be selected, for example, from one or more of spray coating, spin coating, and the like.

<Example 3>
The cover plate with bendable regions according to this embodiment comprises a cover body 10, as shown in FIG.
The second side 102 of the cover body 10 is formed with at least one recess 20 in the foldable area.
On the first surface 101 of the cover body 10, a first uneven structure 50 is formed in a foldable region.
At least three film layers 30 are formed on the second surface 102 .
The refractive index of the film layer 30 is alternately set between a low refractive index and a high refractive index in the direction from the first surface 101 to the second surface 102 .

The three film layers 30 are, for example, a first film layer 301, a second film layer 302 and a third film layer 303 which are laminated in order.
The refractive index of the first film layer 301 is substantially the same as the refractive index of the cover body 10, the refractive index of the second film layer 302 is greater than the refractive index of the first film layer 301, and the refractive index of the second film layer 302 is The index is greater than the refractive index of the third film layer 303 .
A first film layer 301 is in contact with the second surface 102 and the first film layer 301 covers the recess 20 .

The film layer 30 is formed over the second surface 102 to make the cover plate more flexible and less likely to break when folded.
The material of the first film layer 301 may be either an organic material or an inorganic material.
Organic materials can be selected from polyurethane (PU), polyimide (PI), polybutyl acrylate (PBA), polystyrene, polybutadiene, polyethylene, polymethyl methacrylate (PMMA), polycarbonate (PC) and copolymers thereof.
The inorganic material can be selected from silicon dioxide (SiO2), titanium dioxide (TiO2), niobium pentoxide (Nb2O5), the inorganic material has a high refractive index, which can improve the performance of the cover plate at the same time.

Different properties can be obtained with the same base material depending on the preparation process and formulation.
For example, there are more than 10 existing methods for the preparation of PI, and the two-step synthesis method using aromatic tetracarboxylic dianhydride and aromatic diamine as monomers is the most commonly used method for industrial production of PI. The process is relatively mature, there are many kinds of preparation of PI monomer dianhydrides and diamines, and it is possible to obtain PI with different properties by combining different monomers.
The main types of aromatic dianhydrides are homophthalic acid, ether dianhydrides, ketone dianhydrides, biphenyl dianhydrides and fluorine dianhydrides.

A different material can be selected for each layer, or an inorganic material or an organic material can be used for all layers, or a plurality of layers can be used for the organic layer and the inorganic layer.
For example, in the case of an ultra-thin cover plate, it is possible to enhance the mechanical properties of the cover plate by laminating an inorganic material layer on the lower layer, and it is possible to form an organic layer between the inorganic layer and the cover plate. , the mechanical properties of the entire cover plate can be further optimized.

Parallax problems can be further improved by means of adjusting the refractive index.
By using a combination of a high refractive index and a low refractive index, it is possible to obtain the effect of canceling reflected light.
There is no restriction on the magnitude of the refractive index between different layers, and it is possible to use the same organic material for the low refractive index layers and the same inorganic material for the high refractive index layers.

It is also possible to optimize the preparation method and improve preparation efficiency.
For example, if the first film layer 301 is made of a material with a refractive index similar to or the same as that of the cover body 10, light is not refracted in the surface region of the recess 20, so the refractive index difference between the first region and the second region is can be eliminated and a good display effect can be obtained.

The difference in refractive index between the first film layer 301 and the cover body 10 is preferably -0.1 to 0.1. It is possible to reduce the problem of parallax caused by the difference in height (step).

The material and the number of layers of the film layer 30 are not limited, and can be appropriately selected according to the device to be used and the manufacturing method.
Differences in the material and the number of layers of the film layer 30 directly affect the mechanical properties of the cover plate and the parallax phenomenon due to steps.

FIG. 10 shows a schematic diagram in which the problem of visibility is improved by film layers 30 having different refractive indices.
Due to the transmission and reflection properties of the film layer 30, the light from the display module can be reflected between the cover body 10 and the film layer 30 to achieve a uniform light distribution effect.

In addition, at the boundary between the cover body 10 and the film layer 30, a plurality of reflected lights exist, and if the difference between the optical regions satisfies 2nd=mλ−1/(2λ), the reflected lights cancel each other out, and the transmittance increases. improves.
Specifically, fine particles such as inorganic fine particles and organic fine particles can be used in the film layer 30, and vapor deposition and coating can be performed by preparing a solution of the organic fine particles.

When the light from the display module reaches the surface of the recess 20, light scattering can be achieved through the fine particles of the film layer 30, while the refractive index of the film layer 30 made of quartz glass, high silica glass, soda lime glass, etc. is covered. Since it is the same as the body 10, it is possible to further optimize the parallax problem.

A cover plate with bendable regions can be manufactured by the steps shown in FIG.

(S31)
The cover body 10 is fixed and attached to the processing apparatus.
The cover body 10 is preferably made of glass.

(S32)
At least one recess 20 is formed in the bendable area of the second surface 102 of the cover body 10 .
Means for forming the recesses 20 can be selected from mechanical cutting or chemical etching.

(S33)
A first concave-convex structure 50 is formed in the bendable region of the first surface 101 of the cover body 10 .
A means for forming the first concave-convex structure 50 is etching.
In the step of forming the first concave-convex structure 50, an ink protective layer is formed on the non-etching regions, and the ink protective layer is removed after the etching is completed.

(S34)
A first film layer 301 is formed on the second surface 102 .
Means for forming the first film layer 301 include, but are not limited to, coating or vapor deposition.
The first film layer 301 should also be completely formed in the recesses 20 in order to obtain a better parallax cancellation effect.

However, in the process of forming the first film layer 301 , gaps may be formed on the surface of the recesses 20 , and in this case, the first film layer 301 does not completely contact the recesses 20 .
In this case, parallax occurs due to the difference in the refractive index of the air existing in the gap between the surface of the concave portion 20 and the first film layer 301 .

Therefore, the inclination angle of the cover body 10 is adjusted so that air does not enter between the first film layer 301 and the surface of the recess 20, and the recess 20 is sufficiently filled with the material of the first film layer 301. .
Specifically, the horizontal cover body 10 is tilted at both ends thereof in the manner of a balance with the central portion of the concave portion 20 as a fulcrum.
By tilting the cover body 10 in this way, the first film layer 301 can be uniformly formed over the entire surface of the recess 20 and air can be prevented from entering the surface of the recess 20 .

The first film layer 301 can be formed using, for example, a sputtering apparatus as shown in FIG.
The sputtering apparatus holds the cover body 10, and the both end portions of the cover body 10 are fixed to the ceiling portion in the chamber at the support portion tilted in the vertical direction of FIG. and a link member whose one end is fixed to the ceiling part in the chamber and whose other end is attached to the holding part on the left side (leftward direction in FIG. 12) of the fulcrum of the holding part, the link In a configuration in which the member expands and contracts by driving force of a motor or the like, by expanding and contracting the link member, the left and right ends of the holding portion can be alternately tilted in the vertical direction in FIG. 12 accordingly.

S301 (Figure 9 or Figure 13)
The cover body 10 is fixed to the rotation support part in the chamber while being held by the holding part.
By extending and contracting the link member, the cover body 10 has both left and right ends alternately tilted in the vertical direction with the rotation support portion as a fulcrum.
For example, centering on the center line of the recess 20, it can be tilted at 45 degrees with respect to the horizontal direction.

S302 (Figure 9 or Figure 13)
An organic polymer material is used as the target.
The vacuum sputtering conditions are, for example, as follows.
RF power 1-2KW, sputtering gas pressure 0.6-1.0Pa, base vacuum pressure 5.0×10 ^-4 Pa.

S303 (Figure 9 or Figure 13)
In the sputtering process, the first film layer 301 is formed on the cover body 10 while tilting the left and right ends of the holding part that holds the cover body 10 in the vertical direction at a constant speed with the rotation support part as a fulcrum.

(S35)
A second film layer 302 and a third film layer 303 are sequentially formed on the first film layer 301 .
The method of forming the second film layer 302 and the third film layer 303 is not limited, and a method such as coating or vapor deposition can be selected, but the method is not limited to this.

<Example 4>
The cover plate having foldable regions according to this embodiment includes a cover body 10, as shown in FIG.
The second side 102 of the cover body 10 is formed with at least one recess 20 in the foldable area.
On the first surface 101 of the cover body 10, a first uneven structure 50 is formed in a foldable region.
The cross section of the portion of the cover body 10 where the concave portion 20 is formed is curved as shown in FIG.
A second concave-convex structure 60 is formed on the curved surface (the surface of the concave portion 20).

The distribution density of the unevenness of the second uneven structure 60 gradually increases from the central portion of the concave portion 20 toward both ends.
The central portion of the recess 20 has coarse unevenness, and both end surfaces of the recess 20 have fine unevenness.
Therefore, the refraction effect in the central portion is enhanced relative to that in both ends, and the light incident on the concave portion 20 can be made uniform.

The first uneven structure 50 and the second uneven structure 60 are uneven.
The shape of the unevenness is a geometric shape, and examples thereof include rectangles, triangles, circles, ellipses, and the like.
Such irregularities can be formed irregularly or regularly, and these irregularities can be distributed irregularly or regularly.

A first film layer 301 is formed on the second surface 102 , and the first film layer 301 covers the recess 20 .
The first film layer 301 is made of an organic polymer material, and by selecting a material having a refractive index similar to or the same as that of the cover body 10, light is not refracted in the surface region of the concave portion 20, so that the left side of FIG. A good display effect can be obtained by eliminating the refractive index difference between the first area showing the path of the reflected light and the second area showing the path of the reflected light on the right side of FIG.

A cover plate with bendable regions can be manufactured by the steps shown in FIG.

(S41)
The cover body 10 is fixed and attached to the etching apparatus.
The cover body 10 is preferably made of glass.

(S42)
At least one recess 20 is formed in the bendable area of the second surface 102 of the cover body 10 .
The concave portion 20 is a curved concave surface, and the section of the portion of the cover body 10 where the concave portion 20 is formed is curved.

(S401)
In the etching process for forming the recesses 20, the etching speed and etching time are controlled, and the spray gun is moved at a constant speed to form the recesses 20 with a constant recess.
Preferable conditions for the etching step are an etchant temperature of 25 to 30° C., a spray pressure of 0.1 to 0.8 Pa, a spray flow rate of 10 to 15 sccm, and a spray time of 5 to 10 minutes.

(S43)
A second uneven structure 60 is formed on the surface of the recess 20 .
The distribution density of the recesses in the second uneven structure 60 gradually increases from the central portion of the recesses 20 toward both ends.

An etching process for forming the second concave-convex structure 60 is performed as follows.

(S402)
An etchant is sprayed onto the cover body 10 to roughen the concave portions 20 .
Specifically, by spraying the etchant at a low flow rate with a low density in the central portion of the concave portion 20, unevenness with a low density is formed in the central portion of the concave portion 20. FIG.
Preferable conditions for the etching step are an etchant temperature of 25 to 30° C., a spray pressure of 0.1 to 0.8 Pa, a spray flow rate of 10 to 15 sccm, and a spray time of 3 to 8 minutes.
Move the spray gun at a constant speed.

(S403)
An etchant is sprayed onto the cover body 10 to form the curved surface of the concave portion 20 deeper.
Specifically, by increasing the density of the etchant at both ends of the recess 20 and spraying the etchant at a high flow rate, dense unevenness is formed at both ends of the recess 20 .
Preferable conditions for the etching step are an etching solution temperature of 25 to 30° C., a spray pressure of 1 to 1.5 Pa, a spray flow rate of 25 to 30 sccm, and a spray time of 3 to 5 minutes.
The spray gun moves faster in the center and slower at the ends.

A cover plate with foldable regions can also be manufactured by the following steps.

(S44)
A first concave-convex structure 50 is formed in the bendable area of the first surface 101 of the cover plate.
A means for forming the first concave-convex structure 50 is etching.
In the step of forming the first concave-convex structure 50, an ink protective layer is formed on the non-etching regions, and the ink protective layer is removed after the etching is completed.

(S45)
A sputtering device is used to form a first film layer 301 on the second surface 102 .

(S401)
The cover body 10 is fixed to the rotation support part in the chamber while being held by the holding part.
By extending and contracting the link member, the cover body 10 has both left and right ends alternately tilted in the vertical direction with the rotation support portion as a fulcrum.
For example, centering on the center line of the recess 20, it can be tilted at 45 degrees with respect to the horizontal direction.

(S402)
An organic polymer material is used as the target.
The vacuum sputtering conditions are, for example, as follows.
RF power 1-2KW, sputtering gas pressure 0.6-1.0Pa, base vacuum pressure 5.0×10 ^-4 Pa.

(S403)
In the sputtering process, the first film layer 301 is formed on the cover body 10 while tilting the left and right ends of the holding part that holds the cover body 10 in the vertical direction at a constant speed with the rotation support part as a fulcrum.

SUMMARY OF THE INVENTION The present invention provides a foldable display panel that includes a display module and a cover plate having a foldable area positioned over the display module.
The display panel may be an active light emitting display panel, such as an OLED display panel, an Active-Matrix Organic Light Emitting Diode (AMOLED) display panel, a passive matrix OLED display panel, a Quantum Dot Light Emitting Diode (QLED) display panel. , and so on.

The display panel may be a liquid crystal display panel, and the type of display panel is not limited. Vertical electric field type liquid crystal display such as Twisted Nematic (TN) type liquid crystal display panel, Multi-domain Vertical Alignment (MVA) type liquid crystal display panel, etc. A panel is fine.
Examples include horizontal electric field liquid crystal panels such as MVA (alignment) type liquid crystal panels, FFS (fringe field switching) type liquid crystal panels, and IPS (in-plane switching) type liquid crystal panels.

The present invention provides a display device comprising a foldable display panel as described above.
In one or more exemplary embodiments of the present application, for example, the display device may be a computer monitor, laptop computer, digital camera, cell phone handset, smart phone, tablet terminal (computer), television, personal digital assistant device, multimedia It can be applied to players, navigation system devices, game machines, videophone terminals, and the like.

"Length", "Width", "Top", "Bottom", "Front", "Back", "Left", "Right", "Vertical", "Horizontal", "Inner", "Outer", etc. The terminology indicates the orientation or positional relationship shown in the accompanying drawings, and is for the sole purpose of facilitating and simplifying the description of the present invention, where the referenced device or element has a particular orientation and in a particular orientation. It is not intended to imply or imply that the invention must be constructed or operative, and is not a limitation of the invention.
Also, the terms "first" and "second" are used for descriptive purposes only, indicating their relative importance or specifying the number of implied technical features. isn't it.

Thus, functions qualified by "first" and "second" can either explicitly or implicitly include one or more functions.
In the description of the present invention, "plurality" means two or more, unless explicitly and specifically defined.
Technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art of the present invention, unless otherwise defined.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
As used herein, the term "set" refers to both a direct connection between one component and another component and a connection between one component and another component through an intermediate component. do.
Features described herein in one embodiment may apply to other embodiments, either alone or in combination with other features, unless the feature is not applicable in other embodiments or is specified otherwise. can be
While the present invention has been described in terms of embodiments, the above-described embodiments are used for illustration and description only and are not intended to limit the scope of the invention to the described embodiments.

Claims (8)

A cover plate having a foldable area for covering a display module, comprising:
The cover plate consists of a cover body made of various ultra-thin glass materials having a first surface and a second surface,
The first surface has a first uneven structure consisting of a plurality of fine unevenness in a bendable region,
the second surface has at least one recess formed in the foldable region;
A second uneven structure is formed on the surface of the recess,
In the second concave-convex structure, a plurality of fine concave-convex structures are formed sparsely in the central portion of the concave portion and densely on both side portions of the concave portion.
A cover plate having a bendable region, characterized in that: The second surface is formed with at least three film layers,
The refractive index of the film layer is alternately set between a low refractive index and a high refractive index in the direction from the first surface to the second surface.
A cover plate with foldable regions according to claim 1, characterized in that: The three film layers on the second side are
A first film layer, a second film layer, and a third film layer having different refractive indices are laminated,
The refractive index of the first film layer is approximately the same as the refractive index of the cover body,
the refractive index of the second film layer is greater than the refractive index of the first film layer;
the refractive index of the second film layer is greater than the refractive index of the third film layer;
3. A cover plate with foldable regions as claimed in claim 2. The first film layer is
4. A cover plate having foldable regions according to claim 3, wherein the cover plate with foldable regions covers the recess formed in the second surface while in contact with the second surface. The first uneven structure is
Randomly formed on the first surface, the size of the plurality of fine unevenness of the first uneven structure is 0.1 to 2 μm,
A cover plate with foldable regions according to claim 1, characterized in that: a step of fixing and mounting the cover body;
forming at least one recess in the bendable area of the second surface of the cover body;
a step of forming a rough-processed second uneven structure on the surface of the recess;
so that the distribution density of the recesses of the second uneven structure gradually increases from the center of the recess toward both ends,
In the rough processed second uneven structure,
In the center of the recess , the moving speed of the spray gun that sprays the etchant is increased to form unevenness with a small distribution density,
a step of slowing down the moving speed of the spray gun for spraying the etchant on both sides of the recess to form unevenness with a high distribution density;
forming a first concave-convex structure in the foldable region of the first surface;
A method of manufacturing a cover plate having a bendable region according to any of claims 1 to 5, comprising: a display module;
a cover plate having a bendable region according to any one of claims 1 to 5, arranged on the display module;
A display panel comprising: A display device comprising the display panel according to claim 7 .

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