CN106019449A - Polarizing film layer, display device and manufacturing method thereof - Google Patents

Abstract

The invention discloses a polarizing film layer, a display device and a manufacturing method thereof. Wherein, the polarizing film layer is used to be arranged on the light-emitting side of the display panel, including: a first alignment film, a second alignment film opposite to the first alignment film, and a second alignment film located between the first alignment film and the second alignment film. The liquid crystal layer between the two alignment films, the liquid crystals in the liquid crystal layer can be arranged along the predetermined alignment direction of the first alignment film and the predetermined alignment direction of the second alignment film. Through the present invention, the effect of improving the bending radius of the flexible display and the resistance performance in high temperature, high humidity and other environments is achieved.

Description

Polarizing film layer, display device and manufacturing method thereof

technical field

The invention relates to the field of display technology, in particular to a polarizing film layer, a display device and a manufacturing method thereof.

Background technique

At present, there are many functional film layers attached to the display substrate (Panel) of flexible displays, mainly including polarizers, touch screens, protective films, etc. Among them, the function of polarizers is to reflect natural light from the external environment into the display substrate. The light absorption of the substrate is shown. For ease of understanding, please refer to Figure 1 (Figure 1 is a schematic diagram of the film layer structure of a flexible display screen according to the prior art), in the film layer structure shown in Figure 1, the thickness of the touch screen and protective layer is generally about 100um, and The thickness of the polarizer is generally about 200um, and the smallest is about 100um. Therefore, the thickness of the polarizer is relatively large, which will easily cause the overall flexible display to bear greater stress when the flexible display is bent. Moreover, at present, Optical Clear Adhesive (OCA) is usually used to attach the various functional film layers together. Since the thickness of the optical adhesive itself is relatively large and the number of layers is large, the thickness of the overall flexible display is further increased. As a result, the bending radius of the flexible display is small, and it is impossible to realize folding. Excessive bending times are prone to cracking of the film layer and damage to the functional film layer. Moreover, since the polarizer uses specific materials, the properties of these specific materials lead to poor tolerance of the polarizer in high temperature, high humidity and other environments.

For the above-mentioned technical defects, the prior art does not provide an effective solution.

Contents of the invention

The main purpose of the present invention is to provide a technical solution for a flexible display device that can reduce the bending radius of the flexible display, avoid cracking or damage of the film layer easily caused by too many times of bending, and realize folding.

In order to achieve the above object, according to one aspect of the present invention, a polarizing film layer is provided for being arranged on the light exit side of the display panel, comprising: a first alignment film, a second alignment film opposite to the first alignment film film, and a liquid crystal layer located between the first alignment film and the second alignment film, the liquid crystal in the liquid crystal layer can be aligned along the predetermined alignment direction of the first alignment film and the predetermined alignment direction of the second alignment film aligned in the direction of orientation.

Preferably, the polarizing film layer further includes: a sealant disposed between the first alignment film and the second alignment film, the sealant surrounds the liquid crystal layer and is located on the second alignment film. An oriented film and an edge region of the second oriented film.

Preferably, the thickness of the polarizing film layer is less than or equal to 50um.

Preferably, the thickness of the polarizing film layer ranges from 5um to 8um.

According to another aspect of the present invention, a display device is provided, which includes a display panel, and the above-mentioned polarizing film layer arranged on the light-emitting side of the display panel.

Preferably, the first alignment film of the polarizing film layer is formed on the substrate on the light-emitting side of the display panel.

Preferably, the display device further includes: a touch panel disposed on the light emitting side of the polarizing film layer.

Preferably, the second alignment film of the polarizing film layer is formed on the substrate of the touch panel facing the polarizing film layer.

Preferably, the display panel is a flexible display panel.

Preferably, the display device further includes: a protective cover disposed on the side of the touch panel facing away from the polarizing film layer, and optical glue between the touch panel and the protective cover.

According to still another aspect of the present invention, a method for manufacturing a display device is provided, the display device includes a display panel and a touch panel, and the method includes: forming a display panel with a first predetermined orientation on the substrate on the light-emitting side of the display panel. Direction of the first alignment film; on the substrate of the touch panel that needs to face the side of the display panel, a second alignment film with a second predetermined alignment direction is formed; on the first alignment film and the second alignment film A liquid crystal layer and a sealant are formed between them, the sealant surrounds the liquid crystal layer and is located at the edge regions of the first alignment film and the second alignment film, and the liquid crystal in the liquid crystal layer can aligned along the first predetermined orientation direction and the second predetermined orientation direction.

Preferably, the process of forming the first alignment film includes: coating a layer of alignment material on the substrate on the light-emitting side of the display substrate; curing the coated alignment material to obtain a first alignment layer; performing a rubbing operation on the first alignment layer, and then performing a cleaning operation on the first alignment layer to form a thin film having the first alignment layer.

Preferably, the process of forming the second alignment film includes: coating a layer of alignment material on the substrate of the touch panel that needs to face the side of the display substrate; curing the coated alignment material to obtain a first A second alignment layer: performing a rubbing operation on the second alignment layer according to the second predetermined alignment direction, and then performing a cleaning operation on the second alignment layer to form a thin film having the second alignment layer.

Preferably, the process of forming the liquid crystal layer includes: dripping liquid crystal on the first alignment film;

Coating a sealant on the edge of the second orientation film; according to the direction of the second orientation film towards the first orientation film, abutting the second orientation film onto the first orientation film ; hot pressing the second alignment film and the first alignment film to form the liquid crystal layer and the sealant.

Preferably, the method further includes: forming optical glue on the substrate of the touch panel facing away from the display panel; and forming a protective cover on the optical glue.

Compared with the prior art, the polarizing film layer, the display device and the manufacturing method thereof according to the present invention use liquid crystal material instead of the structure of the polarizer layer and the optical adhesive layer, so that the flexible display panel can reduce the overall thickness while It also has the optical functional characteristics of polarized light, so that display products that can be bent at a small angle or foldable can be realized.

Description of drawings

Fig. 1 is a schematic diagram of a film layer structure of a flexible display screen according to the prior art;

Fig. 2 is a schematic structural view of a polarizing film layer according to an embodiment of the present invention;

3 is a flow chart of a method for manufacturing a display device according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of manufacturing process steps of a display device according to an embodiment of the present invention.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Liquid crystals can be classified into thermotropic liquid crystals and lyotropic liquid crystals. Thermotropic liquid crystal refers to a liquid crystal formed by a single compound or a small number of compounds through a homogeneous mixture. This liquid crystal only shows a liquid crystal phase within a certain temperature range. For example, the molecular weight of a typical long rod-shaped thermotropic liquid crystal is generally 200-500g /mol or so. Lyotropic liquid crystal is a liquid crystal formed by two or more compounds including solvent compounds. This liquid crystal appears in a liquid crystal phase when the concentration of solute molecules in the solution is within a certain range. Among them, the main factor that causes long-range ordering of molecules is The reason is the interaction between solute and solvent molecules. At present, the scope of application of optical physical properties of liquid crystals mainly includes anisotropy, optical activity, properties that can change the direction of light polarization, birefringence and circular dichroism.

Based on the characteristics of the liquid crystal itself, and the fact that the film layer structure shown in Figure 1 is difficult to achieve a bendable product form, in the embodiment of the present invention, the film layer structure shown in Figure 1 is carried out mainly by using the property that the liquid crystal can change the polarization direction of light. Improvement, in order to achieve the function of replacing the polarizer layer by the liquid crystal layer, and achieve the purpose of reducing the thickness of the flexible display screen.

An embodiment of the present invention provides a polarizing film layer, which is arranged on the light-emitting side of a display panel. Figure 2 is a schematic structural view of a polarizing film layer according to an embodiment of the present invention, as shown in Figure 2, the polarizing film layer includes: a first alignment film 1, a second alignment film 2 opposite to the first alignment film 1 , and the liquid crystal layer 3 between the first alignment film 1 and the second alignment film 2, the liquid crystal in the liquid crystal layer 3 can be aligned along the predetermined alignment direction of the first alignment film 1 and the second The predetermined orientation directions of the orientation film 2 are aligned.

In practical applications, when forming the first alignment film 1 and the second alignment film 2, it is possible to use organic polymer alignment materials, such as polyimide (PAA), photosensitive glue, etc., because These films are very thin, and can be formed by coating materials such as PAA or photosensitive adhesive on a pre-provided glass substrate, and then performing a curing process.

As a preferred example, the polarizing film layer may further include: a sealant 4 disposed between the first alignment film 1 and the second alignment film 2, the sealant 4 surrounds the liquid crystal layer 3 and located at the edge regions of the first oriented film 1 and the second oriented film 2.

In the structure of the polarizing film layer, the sealant 4 plays the role of supporting the whole structure. In practical application, after the first alignment film 1 and the second alignment film 2 are formed, they can be respectively The first alignment film 1 or the second alignment film 2 is coated with a frame sealant, and after the liquid crystal filling process is completed and the liquid crystal layer 3 is formed, the first alignment film 1 or the second alignment film The oriented film 2 is combined and heat-pressed, and the frame-sealing glue 4 can be formed by the frame-sealing glue.

Since the first oriented film 1, the second oriented film 2 and the sealant 4 are all completed by a coating process, their thicknesses are all very thin (generally between a few tenths of a micron to several microns), and The thickness of the liquid crystal layer 3 composed of liquid crystal molecules is also very thin, so compared with the existing polarizer, the finally formed polarizing film layer has a very obvious advantage of being thin, which will eventually reduce its application in flexible display screens. The bending radius on the screen greatly improves the number of bending times and the life of the flexible display.

In order to effectively reduce the thickness of the polarizing film layer, in a preferred implementation manner of the embodiment of the present invention, the thickness of the polarizing film layer may be set to be less than or equal to 50 um. The thickness of each film can be designed according to the process requirements.

Of course, if it is desired to reduce the thickness of the polarizing film layer to the greatest extent, in the embodiment of the present invention, the thickness range of the polarizing film layer can be further set to 5um˜8um. Usually, since the thickness of the liquid crystal is very small, and the thickness of the alignment film (the first alignment film 1 and the second alignment film 2) is also very small, therefore, for realizing a polarized light with a thickness between 5um and 8um Coating is easy.

Compared with the thickness of the traditional polarizer, which is between 100um and 200um, the thickness of the above-mentioned polarizing film layer is greatly reduced. After it is applied to the flexible display substrate, the thickness of the flexible display substrate will be greatly reduced, which will inevitably reduce the bending of the flexible display substrate. Radius, and easy to achieve collapsible.

On the basis of the above-mentioned polarizing film layer, the present invention also provides a display device, which includes a display panel, and the above-mentioned polarizing film layer that can be arranged on the light-emitting side of the display panel. The main improvement of the display device is that the above-mentioned polarizing film layer is used as its polarizing device, and the advantages of the display device are also reflected by the above-mentioned polarizing film layer.

Since the above-mentioned polarizing film layer is composed of a liquid crystal layer and the first alignment film and the second alignment magic wave respectively positioned on both sides of the liquid crystal layer, when the above-mentioned polarizing film layer is used as a polarizing device of a display device, the polarizing film layer The first alignment film may be formed on the substrate on the light-emitting side of the display panel.

As a preferred example, the display device may further include: a touch panel disposed on the light emitting side of the polarizing film layer. Further, the second alignment film of the polarizing film layer may be formed on the substrate of the touch panel facing the polarizing film layer.

In the embodiment of the present invention, the display panel may preferably be a flexible display panel. However, in practical applications, in order to achieve the effect of thinning the display panel, the above-mentioned polarizing film layer can also be applied to a non-flexible display panel.

As a preferred implementation manner, the above display device may further include: a protective cover disposed on the side of the touch panel facing away from the polarizing film layer, and a protective cover located between the touch panel and the protective cover. optical glue.

Disposing the protective cover on the touch panel through optical glue can effectively protect the touch panel from damage caused by external collision or friction during use by the user.

It can be seen that in the above-mentioned display device, the structure of the polarizer layer and the optical adhesive layer is mainly replaced by liquid crystal material, so that the flexible display panel has the optical function characteristic of polarized light while realizing the overall thickness reduction, so that the flexible display panel can be realized. Display products with small folding angle or foldable.

Corresponding to the above display device, an embodiment of the present invention further provides a method for manufacturing a display device, where the display device includes a display panel and a touch panel. FIG. 3 is a flow chart of a method for manufacturing a display device according to an embodiment of the present invention. As shown in FIG. 3 , the process includes the following steps (step S302-step S306):

Step S302, forming a first alignment film with a first predetermined alignment direction on the substrate on the light-emitting side of the display panel;

Step S304, forming a second alignment film with a second predetermined alignment direction on the substrate of the touch panel that needs to face the side of the display panel;

Step S306, forming a liquid crystal layer and a sealant between the first alignment film and the second alignment film, the sealant surrounds the liquid crystal layer and is located between the first alignment film and the second alignment film In the edge region of the second alignment film, the liquid crystals in the liquid crystal layer can be aligned along the first predetermined alignment direction and the second predetermined alignment direction.

In an embodiment of the present invention, the process of forming the first alignment film may include the following steps:

A1. Coating a layer of alignment material on the substrate on the light-emitting side of the display substrate;

A2, curing the coated alignment material to obtain a first alignment layer;

A3. Perform a rubbing operation on the first alignment layer according to the first predetermined alignment direction, and then perform a cleaning operation on it to form a thin film having the first alignment layer.

In an embodiment of the present invention, the process of forming the second alignment film may include the following steps:

B1. Coating a layer of orientation material on the substrate of the touch panel that needs to face the side of the display substrate;

B2, curing the coated alignment material to obtain a second alignment layer;

B3. Perform a rubbing operation on the second alignment layer according to the second predetermined alignment direction, and then perform a cleaning operation on it to form a thin film having the second alignment layer.

In an embodiment of the present invention, the process of forming the liquid crystal layer may include the following steps:

C1. Dropping liquid crystals on the first alignment film;

C2. Coating a sealant on the edge of the second oriented film;

C3. According to the direction that the second oriented film faces the first oriented film, affix the second oriented film to the first oriented film;

C4. Hot pressing the second alignment film and the first alignment film to form the liquid crystal layer and the sealant.

Of course, after the touch panel is formed, optical glue can also be formed on the substrate of the touch panel facing away from the display panel, and then a protective cover can be formed on the optical glue, so as to effectively The effect of protecting the touch panel from damage caused by external collision or friction during use by the user.

In order to further understand the manufacturing process of the above display device, please refer to FIG. 4. FIG. 4 is a schematic diagram of the manufacturing process steps of the display device according to an embodiment of the present invention. As shown in FIG. 4, when the display panel (Panel) is packaged, respectively Clean the surface of the Panel and the touch substrate, and then coat the surface of the Panel and the touch substrate with an organic polymer orientation material (such as polyimide, or orientation materials such as photosensitive glue), and coat a layer on the surface of the Panel and the touch substrate Uniform alignment layer (i.e. the above-mentioned first layer and second alignment layer), and then coat the sealing gel on the edge area around the Panel and the touch substrate, and then cure the two alignment layers and the sealing gel, through high temperature The treatment cures the alignment layer and the sealing glue. Next, rub the surfaces of the two alignment layers with a material such as flannelette in a specific direction, so that the liquid crystal molecules can be arranged on the surface of the alignment layer along the rubbing direction of the alignment layer in the future. objects, take cleaning steps to remove the contaminants. Then, attach the Panel and the touch substrate, perform hot pressing and pouring, and finally form a polarizing structure and a touch substrate on the display panel, and finally form a protective cover to protect the touch substrate.

In the embodiment of the present invention, the physical and optical characteristics of liquid crystals are used to introduce liquid crystal materials into the flexible display structure. Since the liquid crystal materials have an intermediate state of some properties of crystals and liquids, they have orderly orientation and fluidity of liquids, making them polarized. and bending lubricity, so it can replace the polarizer layer and OCA layer in the flexible display structure. While having a polarizing effect, reducing the overall thickness of the flexible display will greatly improve the bending characteristics of the flexible display and reduce the bending radius. , The number of bending times is increased.

The above description is a preferred embodiment of the present invention, it should be pointed out that for those skilled in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications are also It should be considered as included within the protection scope of the present invention.

Claims (15)

1. A polarizing film layer, used to be arranged on the light-emitting side of the display panel, is characterized in that, comprising: A first alignment film, a second alignment film opposite to the first alignment film, and a liquid crystal layer located between the first alignment film and the second alignment film, the liquid crystal in the liquid crystal layer can move along aligned along the predetermined orientation direction of the first oriented film and the predetermined orientation direction of the second oriented film. 2. polarizing film layer according to claim 1, is characterized in that, also comprises: A sealant disposed between the first alignment film and the second alignment film, the sealant surrounds the liquid crystal layer and is located between the first alignment film and the second alignment film edge area. 3. The polarizing film layer according to claim 2, characterized in that, the thickness of the polarizing film layer is less than or equal to 50um. 4 . The polarizing film layer according to claim 3 , wherein the thickness of the polarizing film layer ranges from 5 um to 8 um. 5 . A display device, characterized by comprising a display panel, and the polarizing film layer according to any one of claims 1 to 4 arranged on the light-emitting side of the display panel. 6 . 6 . The display device according to claim 5 , wherein the first alignment film of the polarizing film layer is formed on the substrate on the light emitting side of the display panel. 7 . The display device according to claim 6 , further comprising: a touch panel disposed on the light emitting side of the polarizing film layer. 8 . The display device according to claim 7 , wherein the second alignment film of the polarizing film layer is formed on the substrate of the touch panel facing the polarizing film layer. 9. The display device according to any one of claims 5 to 8, wherein the display panel is a flexible display panel. 10. The display device according to claim 7 or 8, further comprising: A protective cover disposed on the side of the touch panel facing away from the polarizing film layer, and an optical glue between the touch panel and the protective cover. 11. A manufacturing method of a display device, the display device comprising a display panel and a touch panel, characterized in that the method comprises: forming a first alignment film with a first predetermined alignment direction on the substrate on the light-emitting side of the display panel; forming a second alignment film with a second predetermined alignment direction on the substrate of the touch panel that needs to face the side of the display panel; A liquid crystal layer and a sealant are formed between the first alignment film and the second alignment film, and the sealant surrounds the liquid crystal layer and is located between the first alignment film and the second alignment film. In the edge region of the alignment film, the liquid crystals in the liquid crystal layer can be aligned along the first predetermined alignment direction and the second predetermined alignment direction. 12. The method according to claim 11, wherein the process of forming the first alignment film comprises: Coating a layer of alignment material on the substrate on the light-emitting side of the display substrate; Curing the coated alignment material to obtain a first alignment layer; According to the first predetermined alignment direction, the first alignment layer is rubbed, and then cleaned to form a thin film having the first alignment. 13. The method according to claim 11, wherein the process of forming the second oriented film comprises: Coating a layer of alignment material on the substrate of the touch panel that needs to face the side of the display substrate; Curing the coated alignment material to obtain a second alignment layer; According to the second predetermined orientation direction, the second orientation layer is rubbed and then cleaned to form the second orientation film. 14. The method according to claim 11, wherein the process of forming the liquid crystal layer comprises: dripping liquid crystal on the first alignment film; Coating a sealant on the edge of the second orientation film; According to the direction in which the second orientation film faces the first orientation film, the second orientation film is attached to the first orientation film; The second alignment film and the first alignment film are hot-pressed to form the liquid crystal layer and the sealant. 15. The method according to any one of claims 11 to 14, further comprising: forming optical glue on the substrate of the touch panel facing away from the display panel; A protective cover is formed on the optical glue.