WO2015174573A1

WO2015174573A1 - Surface anchoring energy controllable liquid crystal display device, manufacturing method therefor and manufacturing device thereof

Info

Publication number: WO2015174573A1
Application number: PCT/KR2014/005112
Authority: WO
Inventors: 이기동; 문병준; 조정호; 박기웅; 백승민
Original assignee: 동아대학교 산학협력단
Priority date: 2014-05-14
Filing date: 2014-06-11
Publication date: 2015-11-19
Also published as: KR20150130801A; KR101666550B1

Abstract

The present invention relates to a surface anchoring energy controllable liquid crystal display device capable of controlling surface anchoring energy by mixing a photo-alignment agent and reactive mesogen (RM) to induce alignment and polymerization of the RM only with a UV wavelength, a manufacturing method therefor and a manufacturing device thereof, the liquid crystal display device comprising: a first surface anchoring energy control mixing layer formed by mixing the photo-alignment agent, the RM and a photo initiator on a first substrate, achieving photo alignment by UV irradiation of a first wavelength band, and controlling surface anchoring energy by forming a polymer network by UV irradiation of a second wavelength band; a second surface anchoring energy control mixing layer formed by mixing the photo-alignment agent, the RM and the photo initiator on a second substrate, achieving photo alignment by UV irradiation of the first wavelength band, and controlling the surface anchoring energy by forming a polymer network by UV irradiation of the second wavelength band; and a liquid crystal layer located between the first substrate and the second substrate which face each other.

Description

Liquid crystal display device capable of surface fixed energy control, manufacturing method thereof and manufacturing device therefor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device. Specifically, surface alignment is achieved by mixing a photo alignment agent and a reactive mesogen (RM) to induce a polymerization reaction of alignment and RM using only a UV wavelength to control surface fixation energy. A liquid crystal display device capable of energy control, a method of manufacturing the same, and a manufacturing apparatus therefor.

Generally, a liquid crystal display includes a liquid crystal layer having regularly oriented molecules and a liquid crystal alignment film for aligning such liquid crystals is formed from a polymer material.

The polymer material is coated on a substrate such as a transparent electrode to form a liquid crystal alignment film. Generally, a liquid crystal alignment film may be prepared by rubbing a process, ie, rubbing fibers such as nylon or rayon with a polymer film.

Looking at the related art, researches to increase surface fix energy using Reactive Mesogen (RM) have been actively conducted to improve the response speed of LCD panels.

In particular, as shown in FIG. 1, a method of orienting a mixture of polyimide (PI) and RM on a substrate and a method of stacking PI and RM, respectively, as shown in FIG. 2, are representative methods for increasing surface fixation energy.

However, the two methods have in common that a rubbing process should be used for the alignment treatment.

The rubbing process is a method of inducing orientation by direct friction with cloth or fiber, and dust or static electricity are generated to cause loss of electro-optical properties of the liquid crystal display.

Thus, there is a growing interest in practical alternative techniques due to some major drawbacks and limitations of traditional rubbing methods of liquid crystal alignment.

Recently, in order to compensate for this problem, an alignment process using a photoalignment method has been performed.

Therefore, there is a demand for developing a technology for improving surface fixation energy by applying a photoalignment agent.

The present invention is to solve the problems of the liquid crystal display device of the prior art, by mixing a photo alignment agent (RM) (Reactive Mesogen) and induction of the orientation and polymerization of the RM only by UV wavelength surface fixed energy It is an object of the present invention to provide a liquid crystal display device capable of controlling surface fixed energy so as to be controlled, a method of manufacturing the same, and a manufacturing device therefor.

The present invention enables the formation of photo-alignment and polymer network by irradiating UV reacting to each material by using the UV alignment wavelengths of the photo-alignment agent and RM + photoinitiator do not overlap, thereby increasing the efficiency and reproducibility of the manufacturing process. SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid crystal display device and a method of manufacturing the same, and a method for manufacturing the same, which can control the surface fixed energy to improve the operation characteristics of the device through a process.

The present invention enables the formation of optical alignment and polymer networks by selectively using UV light having only a specific wavelength band even when the reaction wavelength bands of materials overlap, thereby improving the efficiency and reproducibility of the manufacturing process, thereby improving the operation characteristics of the device. SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid crystal display, a method of manufacturing the same, and a manufacturing apparatus for the same, capable of controlling the surface fixed energy so as to be improved.

The present invention can improve the efficiency and reproducibility of the manufacturing process by using a filter for UV wavelength separation even if the reaction wavelength bands of materials overlap, thereby improving the operational characteristics of the device in an easy process. It is an object of the present invention to provide a liquid crystal display device capable of controlling the surface fixed energy, a method of manufacturing the same, and a manufacturing device therefor.

The objects of the present invention are not limited to the above-mentioned objects, and other objects that are not mentioned will be clearly understood by those skilled in the art from the following description.

In order to achieve the above object, a liquid crystal display device capable of controlling surface fixation energy according to the present invention is formed by mixing a photoalignment agent, a reactive mesogen (RM), and a photoinitiator on a first substrate, A first surface fixed energy control mixed layer in which photoalignment is performed and a polymer network is formed by UV irradiation in a second wavelength band to control surface fixation energy; a photoalignment agent, a reactive mesogen (RM), and a photoinitiator on a second substrate A second surface fixed energy control mixed layer having mixed and formed, photo-alignment by UV irradiation in a first wavelength band, and a polymer network being formed by UV irradiation in a second wavelength band to control surface fixed energy; And a liquid crystal layer positioned between the first substrate and the second substrate.

Here, the first wavelength band is 300nm ~ 365nm, the second wavelength band is characterized in that 200nm ~ 254nm.

The UV irradiation of the first wavelength band for photo-alignment and the UV irradiation of the second wavelength band for forming the polymer network are equally irradiated with UV in the 250 nm to 450 nm wavelength band, and specified in the UV irradiation step of any one wavelength band. It is characterized by advancing in a state where a filter for passing or blocking UV in a wavelength band is laminated therebetween.

And the surface fixation energy is

Calculated as

Where d is the cell gap, p is the pitch,

: Real twisted angle,

: Liquid crystal alignment angle,

: It is characterized by the torsion constant of the liquid crystal.

According to another aspect of the present invention, there is provided a method of manufacturing a liquid crystal display device capable of controlling surface fixed energy, the method including: preparing a lower substrate and an upper substrate; preparing a photoalignment agent + reactive meogen (RM) + photoinitiator mixture; Coating the mixture on a substrate, and performing soft baking and hard baking to form an optical polyimide layer; irradiating UV in a first polarized wavelength band for photoalignment; Injecting and annealing; Irradiating the UV of the second wavelength band to form a polymer network; characterized in that it comprises a.

And the photo-alignment agent + RM (Reactive Meogen) + photoinitiator mixture is characterized in that prepared in 95.7: 0.05: 4.2wt%.

The first wavelength band is 300nm to 365nm to which the photo-alignment agent reacts, and the second wavelength band is 200nm to 254nm to which the reactive meogen (RM) + photoinitiator reacts.

In the UV irradiation step of the first and second wavelength bands, the UV irradiation step of any one of the wavelength bands is performed in a state in which a filter for passing or blocking the UV of a specific wavelength band is laminated therebetween.

And in the step of forming the optical polyimide layer, soft baking is performed for 2 minutes at a temperature of 100 ℃, hard baking is characterized in that for 1 hour at a temperature of 180 ℃.

According to another aspect of the present invention, there is provided a manufacturing apparatus of a liquid crystal display device capable of controlling surface fixation energy according to the present invention, including: a mixing treatment unit for manufacturing a photoalignment + reactive meogen (RM) + photoinitiator mixture; A baking treatment unit for performing soft baking and hard baking; an optical alignment UV irradiation unit for irradiating linearly polarized UV light of a first wavelength band in which only the optical alignment agent reacts; injecting liquid crystal by bonding the aligned substrate, and ordering the injected liquid crystal Liquid crystal injection and annealing annealing (annealing) to increase the ordering (polymer network forming UV irradiation unit for irradiating the UV of the second wavelength band to which the RM + photoinitiator reacts to form a polymer network; characterized in that it comprises a.

Such a liquid crystal display and a manufacturing method and a manufacturing apparatus therefor capable of controlling the surface fixed energy according to the present invention has the following effects.

First, surface alignment energy can be controlled by mixing photo alignment and reactive mesogen (RM) to induce alignment and polymerization of RM using only UV wavelength.

Second, since the UV wavelength alone induces the orientation and polymerization of the RM, problems caused by dust or static electricity generated in the rubbing process can be solved.

Third, the response speed can be improved by increasing the weak surface fixation energy of the photo-alignment agent using RM, and thus it is applicable to various liquid crystal display devices requiring high transmittance and fast response speed.

Fourth, by using the UV range of the photo-alignment agent and the RM + photoinitiator does not overlap the range of the UV reaction to each material to enable the photo-alignment and polymer network formation.

Fifth, by using UV light of specific wavelength band or by using filter for UV wavelength separation, it is possible to form photo-alignment and polymer network and improve the efficiency and reproducibility of manufacturing process. Can be improved.

1 and 2 is a configuration diagram showing a method of orienting a mixture of Polyimide (PI) and RM of the prior art on a substrate and a method of stacking PI and RM, respectively

3 is a cross-sectional view of a liquid crystal display device capable of controlling surface fixed energy according to the present invention.

4 and 5 is a configuration diagram showing the reaction state according to the use of the UV filter

6 is a block diagram showing a manufacturing process using UV selective irradiation of the liquid crystal display according to the present invention

7 is a flowchart illustrating a manufacturing process of a liquid crystal display device capable of controlling surface fixed energy according to the present invention.

8 is a cross-sectional view of a manufacturing process of a liquid crystal display capable of controlling surface fixed energy according to the present invention.

9 is a configuration diagram of an apparatus for manufacturing a liquid crystal display device capable of controlling surface fixed energy according to the present invention.

Hereinafter, a liquid crystal display capable of controlling surface fixed energy according to the present invention, a manufacturing method thereof, and a preferred embodiment of the manufacturing apparatus therefor will be described in detail.

Features and advantages of the liquid crystal display device and the method for manufacturing the surface-fixed energy control according to the present invention and the manufacturing apparatus therefor will be apparent from the detailed description of each embodiment below.

4 and 5 are configuration diagrams showing the reaction state according to the use of the UV filter, Figure 6 is a configuration diagram showing the manufacturing process using the UV selective irradiation of the liquid crystal display according to the present invention.

The present invention is to mix the photo alignment agent (RM) and reactive methogen (RM) to induce the polymerization reaction of the orientation and RM only by UV wavelength to control the surface fixation energy, UV reaction of the photo-alignment agent and RM + photoinitiator It is to perform photo-alignment and polymer formation by irradiating UV reacting to each material by using the overlapping wavelength range.

The present invention enables the simultaneous formation of a photonic alignment and a polymer network of RMs in one pixel using wavelength bands of different UVs.

In the following description, the liquid crystal display device has a form having a pattern electrode as an example, but the structure and method for improving the surface fixation energy using the photoalignment agent and the RM mixture according to the present invention are not limited to any one specific liquid crystal mode, but the photoalignment agent Naturally, it can be applied to various liquid crystal modes according to the characteristics (horizontal photoalignment agent, vertical photoalignment agent).

In the liquid crystal display according to the present invention, as shown in FIG. 3, a photo alignment agent, a reactive alignment agent (RM), and a photoinitiator are formed on the first substrate 60 having the pattern electrode 50. The first surface fixed energy control mixed layer 40 and the second substrate 10 in which photo-alignment is performed by UV irradiation in one wavelength band, and a polymer network is formed by UV irradiation in a second wavelength band, thereby controlling surface fixed energy. ) Is formed by mixing photo alignment agent, reactive mesogen (RM) and photoinitiator, photo alignment is achieved by UV irradiation in the first wavelength band, and polymer network is formed by UV irradiation in the second wavelength band. And a second surface fixed energy control mixed layer 20 in which surface fixed energy is controlled, and a liquid crystal layer 30 positioned between the first substrate 60 and the second substrate 10 facing each other.

According to the present invention, the first surface fixed energy control mixed layer 40 and the second surface fixed energy control mixed layer 20 are formed by separating the appropriate wavelength band and irradiating UV by using the photoaligning agent and the UV absorption wavelength band of the RM that are different from each other. The surface fixing energy of) is increased to improve the response speed.

The wavelength band of the photo-alignment agent used in one embodiment of the present invention is 300nm, the photoinitiator is 200nm.

Therefore, by inducing photo-alignment with UV exposure of 300nm and forming polymer network of RM through UV-exposure of 200nm, photo-alignment and polymer are separated by separating UV reaction wavelength band of photo-alignment agent and reactive mesogen (RM). Network formation is done within one pixel.

Such a wavelength band is given as an example, and is not limited to the above numerical values, and it is natural that the UV reaction wavelength band of the photoalignment agent and the RM + photoinitiator may be used in various ways depending on the material used.

4 and 5 are configuration diagrams showing the reaction state according to the use of the UV filter.

4 shows a case of irradiating without UV wavelength band, it can be seen that it is difficult to optimize the alignment of the photo-alignment and the formation of the polymer network due to the strong chemical reaction occurs in both the photo-alignment agent and the reactive mesogen (RM) + photoinitiator by UV light have.

On the other hand, when using a UV filter that passes or blocks the UV of a specific wavelength band, as in an embodiment of the present invention, photo-alignment is achieved by UV irradiation of the first wavelength band, UV of the second wavelength band It can be seen that the polymer network is formed by irradiation to control the surface fixation energy.

When the UV wavelength band is classified and irradiated, the optical alignment and the formation of the polymer network are described based on the material properties and the UV wavelength range.

In terms of the physical properties of the material, when the range of UV reaction wavelengths of the photo-alignment agent and RM + photoinitiator used for manufacturing do not overlap, it is possible to perform photo-alignment and polymer network formation by irradiating the reacting UV of each material.

In one embodiment of the present invention, although the photo-alignment agent for irradiating UV of a high wavelength band and the RM + photoinitiator for irradiating UV of a somewhat lower wavelength band, the wavelength bands of the two materials may be interchanged.

Here, in the case of RM, the polymer network is formed by the help of the photoinitiator instead of reacting with the UV itself. Therefore, when considering the reaction wavelength, the UV wavelength band is selected in consideration of the UV wavelength band of the photoinitiator.

In terms of the UV wavelength range, since the UV wavelength is distributed in a wide range (250 nm to 450 nm), it is possible to select the UV light having a specific wavelength band and perform photo-alignment and polymer formation even when the reaction wavelength bands of the materials overlap.

For example, two different UV light sources with narrow wavelength bands are used to separate and irradiate the UV wavelength bands so that photo-alignment and formation of a polymer network can be carried out, or in the case of a UV light source with a broad wavelength band, Optical alignment and polymer network formation can be performed using a filter.

Here, the use of the filter for UV wavelength separation is one example and is not limited to the use of the filter.

As well as the use of filters, other forms and methods can be used to achieve UV wavelength separation.

6 is a block diagram illustrating a manufacturing process using UV selective irradiation of the liquid crystal display according to the present invention.

For manufacturing using UV selective irradiation, spin coating the material layer mixed with the photo-alignment agent and the RM + photoinitiator on the substrate, and the baking process for 1 hour 30 minutes at a temperature of 180 ℃.

Then, the linear UV polarizer and the long pass filter for UV linearly polarized light are placed on the mixed material layer formed on the lower substrate, and photo-alignment is performed by irradiating UV of 365nm.

Subsequently, the lower substrate and the upper substrate are bonded to each other, and after the liquid crystal is injected, UV of 254 nm is irradiated to increase surface fixation energy.

The manufacturing process of the liquid crystal display device capable of controlling the surface fixed energy according to the present invention is as follows.

7 is a flowchart illustrating a process for manufacturing a surface fixed energy control device according to the present invention, and FIG. 8 is a cross-sectional view illustrating a process for manufacturing a surface fixed energy control device according to the present invention.

In the following description, a liquid crystal display device having a pixel electrode line and a common electrode line has been described as an example. Naturally, the present invention can be applied to various liquid crystal modes depending on the characteristics of the photoalignment agent (horizontal photoalignment agent and vertical photoalignment agent).

A lower substrate and an upper substrate having a pixel electrode line and a common electrode line are prepared (S601), and a mixture of photo-alignment agent + Reactive Meogen (RM) + photoinitiator (95.7: 0.05: 4.2 wt%) is prepared (S602).

Subsequently, the prepared mixture is coated on a substrate and then soft baked for 2 minutes at a temperature of 100 ° C. (S603)

And hard baking (Hard baking) for 1 hour at a temperature of 180 ℃ to form an optical polyimide layer (polyimidization formation) (S604).

Subsequently, the linearly polarized UV for photoalignment is irradiated. (S605)

Here, the irradiated UV light irradiates UV of the first wavelength band in which only the photoalignment agent reacts.

As described above, the process of irradiating UV by dividing the wavelength band may use the above-described filter or selectively use UV of the selected wavelength band according to the material properties.

In order to bond the two oriented substrates, inject the liquid crystal (S606), and to increase the ordering of the injected liquid crystal, an annealing process is performed at a temperature of 100 ° C. for 5 minutes (S607).

Subsequently, UV of the wavelength band where the RM + photoinitiator reacts is formed to form a polymer network.

The UV wavelength band, baking temperature, annealing temperature, and time to be irradiated in the liquid crystal display manufacturing process as described above are examples, and may be differently performed depending on the physical properties of the materials used and the pattern design form.

The manufacturing apparatus for manufacturing the liquid crystal display device capable of controlling the surface fixed energy according to the present invention will be described as follows.

The apparatus for manufacturing a liquid crystal display device according to the present invention is a photo-alignment UV irradiation unit and a polymer network formation UV irradiation unit in order to irradiate UV in different wavelength bands in order to proceed with the photo-alignment and polymer network formation by irradiating UV wavelength bands separately It is provided.

Its composition consists of a mixing treatment unit 80 for preparing a mixture of photo-alignment agent + reactive meogen (RM) + photoinitiator (95.7: 0.05: 4.2wt%) and the prepared mixture on a substrate, followed by 2 minutes at a temperature of 100 ° C. Soft baking, and the baking treatment unit 81 for hard baking (Hard baking) for 1 hour at a temperature of 180 ℃, and the linearly polarized UV of the first wavelength band to react only the photo-alignment agent In order to bond the photo-alignment UV irradiation unit 82 to be irradiated with the two oriented substrates, inject the liquid crystal, and increase the ordering of the injected liquid crystal, annealing is performed at a temperature of 100 ° C. for 5 minutes. The liquid crystal injection and annealing unit 83 and the polymer network forming UV irradiation unit 84 for irradiating the UV of the second wavelength band to which the RM + photoinitiator reacts to form the polymer network.

Here, the photo-alignment UV irradiation unit 82 and the polymer network forming UV irradiation unit 84 has been described as an example of the separation configuration, but may be configured integrally when the wavelength band is separated using a filter.

Surface fixed energy control and increase characteristics of the liquid crystal display according to the present invention manufactured using such a configuration and manufacturing process are as follows.

In order to calculate the surface fixed energy control and increase characteristics, the twist angle of the liquid crystal is measured to calculate the surface fixed energy.

In order to strengthen the twisting force of the liquid crystal, chiral dopant materials are generally mixed in the liquid crystal. The twist angle of the liquid crystal when the chiral dopant is mixed can be described as a cell gap (d) / pitch (p). For example, when d / p = 1, the twist angle in the cell gap is 360 °.

In the measurement in the present invention, d / p having a cell gap (d) = 3.2 and a pitch (p) = 24 was measured in a 0.13 state, and the twist angle was 48 °.

By applying the top and bottom liquid crystal alignment angles of the fabricated cells at 30 °, the liquid crystals with the force to turn up to 48 ° by the Chiral dopant are suppressed when the surface fixation energy in the cell increases, The liquid crystal twist state can be maintained.

That is, the surface fixation energy may be calculated by determining how much the twist angle is formed based on the 30 ° alignment direction of the liquid crystal molecules.

The surface fixation energy is calculated as in Equation 1.

Equation 1

here,

: Actual twist angle (= measured Twist angle),

: Liquid crystal alignment angle (= initial alignment angle, 30 °),

: Torsional constant of the liquid crystal (intrinsic physical properties of the liquid crystal used, 6 * 10 ^-12 ).

Table 1

	Rubbing method (Polyimid = PI)	Photo-Alignment method (Photo-PI)	Proposed Photo-alignment method (RM + Photo PI) Before UV	Proposed Photo-alignment method (RM + Photo PI) After UV
Twist angle	31.5 deg.	41 deg.	36 deg.	31.75 deg.
Anchoring energy	2.06x10 ^-5 J / m ²	1.13x10 ^-6 J / m ²	3.78 x 10 ^-6 J / m ²	1.79 x 10 ^-5 J / m ²

From Table 1, it can be seen that when applying the manufacturing process according to the present invention using a photo-alignment agent mixed with RM can have a high surface fixation energy of about 16 times compared to the conventional photo-alignment method. .

Such a liquid crystal display device and a method for manufacturing the surface fixed energy control according to the present invention and a manufacturing apparatus therefor are mixed with a photo alignment agent (RM) and a reactive mesogen (RM) to perform a polymerization reaction of the alignment and RM only by UV wavelength By controlling the surface fixed energy by induction, it is to perform the photo-alignment and polymer formation by irradiating the UV reacting to each material using a range of UV reaction wavelengths of the photo-alignment agent and RM + photoinitiator do not overlap.

It will be understood that the present invention is implemented in a modified form without departing from the essential features of the present invention as described above.

Therefore, the described embodiments should be considered in descriptive sense only and not for purposes of limitation, and the scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the equivalent scope are included in the present invention. It should be interpreted.

The liquid crystal display device and method for manufacturing the surface-fixed energy control according to the present invention, and a manufacturing method therefor are mixed with a photo alignment agent (RM) and a reactive mesogen (RM) to induce a polymerization reaction of the alignment and RM by only the UV wavelength It is to control the surface fixed energy.

Claims

A photoalignment agent, a reactive mesogen (RM), and a photoinitiator are formed on the first substrate, and photoalignment is performed by UV irradiation in a first wavelength band, and a polymer network is formed by UV irradiation in a second wavelength band. A first surface fixed energy control mixed layer in which fixed energy is controlled;

A photoalignment agent, a reactive mesogen (RM), and a photoinitiator are formed on the second substrate, and photoalignment is performed by UV irradiation in a first wavelength band, and a polymer network is formed by UV irradiation in a second wavelength band. A second surface fixed energy control mixed layer in which fixed energy is controlled;

And a liquid crystal layer positioned between the first substrate and the second substrate, which face each other.
The liquid crystal display device according to claim 1, wherein the first wavelength band is 300 nm to 365 nm and the second wavelength band is 200 nm to 254 nm.
The method of claim 1, wherein the UV irradiation of the first wavelength band for photo-alignment and the UV irradiation of the second wavelength band for forming the polymer network are irradiated with UV in the wavelength range of 250 nm to 450 nm. A liquid crystal display capable of controlling surface fixation energy, characterized in that the UV irradiation step is carried out in a state in which a filter for passing or blocking UV of a specific wavelength band is laminated therebetween.
The method of claim 1, wherein the surface fixing energy,

Calculated as

Where d is the cell gap, p is the pitch,
: Real twisted angle,
: Liquid crystal alignment angle,
: A liquid crystal display capable of surface fixed energy control, characterized by a torsional constant of liquid crystal.
Preparing a lower substrate and an upper substrate;

Preparing a photoalignment + reactive meogen (RM) + photoinitiator mixture;

Coating the mixture on a substrate, and performing soft baking and hard baking to form an optical polyimide layer;

Irradiating UV of the first polarized wavelength band for photoalignment;

Bonding the oriented substrates to inject and anneal liquid crystals;

And irradiating UV light in a second wavelength band to form a polymer network.
The method of claim 5, wherein the photo-alignment + reactive meogen (RM) + photoinitiator mixture is prepared at 95.7: 0.05: 4.2 wt%.
6. The surface fixed energy control of claim 5, wherein the first wavelength band is 300 nm to 365 nm to which the photo-alignment agent reacts, and the second wavelength band is 200 nm to 254 nm to which the reactive meogen (RM) + photoinitiator reacts. Method of manufacturing a liquid crystal display device possible.
The method according to claim 5, wherein the UV irradiation in any of the first and second wavelength bands is performed in a state in which a filter for passing or blocking UV in a specific wavelength band is laminated in the UV irradiation step of any one of the wavelength bands. Method of manufacturing a liquid crystal display device capable of controlling the surface fixed energy.
The method of claim 5, wherein in the step of forming the photo polyimide layer,

Soft baking is carried out for 2 minutes at a temperature of 100 ℃, hard baking is carried out for 1 hour at a temperature of 180 ℃, manufacturing method of a liquid crystal display device capable of controlling the surface fixed energy.
Mixing treatment unit for preparing a photo-alignment agent + RM (Reactive Meogen) + photoinitiator mixture;

A baking treatment unit which performs soft baking and hard baking after coating the mixture on a substrate;

Photo-alignment UV irradiation unit for irradiating the linearly polarized UV of the first wavelength band to react only the photo-alignment agent;

A liquid crystal injection and annealing unit for injecting liquid crystals by bonding the oriented substrates and annealing to increase the ordering of the injected liquid crystals;

And a polymer network forming UV irradiation unit for irradiating UV in a second wavelength band in which the RM + photoinitiator reacts to form a polymer network.