KR20150130801A - L c d with controllable surface anchoring energy and method for fabricating l c d, and manufacturing device for l c d - Google Patents

Abstract

The present invention relates to a liquid crystal display device capable of controlling surface fixing energy by mixing a photo alignment and an RM (Reactive Mesogen) and inducing polymerization and reaction of RM by only the UV wavelength, and (Reactive Mesogen) and a photoinitiator are mixed on a first substrate, a light is radiated by UV irradiation in a first wavelength band, and a second wavelength band A first surface-anchoring energy control mixed layer in which a polymer network is formed by UV irradiation of the first wavelength band and surface fixing energy is controlled, a light control agent, a RM (Reactive Mesogen) and a photoinitiator are mixed on a second substrate, A second surface fixed energy in which a polymer network is formed by UV irradiation in the second wavelength band and surface fixing energy is controlled, And a liquid crystal layer disposed between the first substrate and the second substrate facing each other.

Description

Technical Field [0001] The present invention relates to a liquid crystal display device, a method of manufacturing the same,

More particularly, the present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device capable of mixing a photo alignment and a RM (Reactive Mesogen) to induce orientation and RM polymerization reaction at only UV wavelengths, A liquid crystal display device capable of energy control, a manufacturing method thereof, and a manufacturing apparatus therefor.

Generally, a liquid crystal display comprises a liquid crystal layer having molecules oriented in a uniform direction, and a liquid crystal alignment film for orienting such liquid crystal 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. In general, a liquid crystal alignment film can be produced by rubbing a rubbing process, that is, rubbing fibers such as nylon or rayon with a polymer film.

In order to improve the response speed of a liquid crystal display panel, studies have been actively conducted to increase the surface fixing energy using Reactive Mesogen (RM).

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 laminating PI and RM, respectively, as shown in FIG.

However, both of these methods have a common point in using a rubbing process in alignment treatment.

The rubbing process induces orientation by direct friction with cloth or fiber, and dust or static electricity is generated, which causes loss of electro-optical characteristics of the liquid crystal display device.

Therefore, there is an increasing interest in practical alternative techniques due to some major drawbacks and limitations of the conventional rubbing method of liquid crystal alignment.

In recent years, an alignment process using a photo alignment method has been performed to overcome this problem.

Therefore, it is required to develop a technique for improving surface fixing energy by applying a light distribution agent.

Korean Patent Publication No. 10-2009-0050099 Korean Patent Publication No. 10-2013-0119589

The present invention solves the problem of such a conventional liquid crystal display device, and it is an object of the present invention to provide a liquid crystal display device in which the photo alignment and the RM (Reactive Mesogen) are mixed, And a method of manufacturing the liquid crystal display device, and a manufacturing apparatus therefor.

The present invention makes it possible to form a photo-alignment and a polymer network by irradiating UVs that react with each material by using the fact that the ranges of the UV reaction wavelengths of the photo-dispersing agent and RM + photoinitiator do not overlap, thereby improving the efficiency and reproducibility of the manufacturing process, The present invention provides a liquid crystal display device capable of controlling the surface fixed energy so as to improve the operation characteristics of the device, a method of manufacturing the same, and a manufacturing apparatus therefor.

The present invention enables optical alignment and polymer network formation by selectively using UV light having only a specific wavelength band even when the reaction wavelength band of the material overlaps, thereby improving the efficiency and reproducibility of the manufacturing process, And to provide a manufacturing method thereof and a manufacturing apparatus therefor. 2. Description of the Related Art

The present invention can improve the efficiency and reproducibility of the manufacturing process by making it possible to form a photo-alignment and a polymer network by using a filter for UV wavelength separation even if the reaction wavelength band of the material overlaps. And a method of manufacturing the liquid crystal display device, and a manufacturing apparatus therefor.

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

In order to accomplish the above object, the present invention provides a liquid crystal display device capable of controlling surface fixed energy, comprising: a first substrate on which a light distribution agent, an RM (Reactive Mesogen) and a photoinitiator are mixed, A first surface fixed energy control mixed layer in which a polymer network is formed by UV irradiation in a second wavelength band and a surface fixing energy is controlled, a second surface fixed energy control mixed layer is formed on the second substrate, a light distribution agent, a RM (Reactive Mesogen) A second surface-anchoring energy control mixed layer formed by mixing UV light of a first wavelength band, a second surface-energetic control mixed layer of which a polymer network is formed by UV irradiation of a second wavelength band to control surface fixing energy, And a liquid crystal layer disposed between the first substrate and the second substrate.

Here, the first wavelength band is 300 nm to 365 nm, and the second wavelength band is 200 nm to 254 nm.

The UV irradiation of the first wavelength band for the photo alignment and the UV irradiation of the second wavelength band for forming the polymer network are performed in the same manner as the UV irradiation of the wavelength band of 250 nm to 450 nm, And a filter for passing or blocking UV in the wavelength band is laminated therebetween.

으로 계산되고,And the surface fixed energy,

Lt; / RTI >

: 실제 꼬인 각,

: 액정정렬 각,

: 액정의 비틀림 상수인 것을 특징으로 한다.Where d is the cell gap, p is the pitch,

: Actual twisted angle,

: LCD alignment angle,

: A twist constant of the liquid crystal.

A method of fabricating a liquid crystal display device capable of controlling surface fixed energy according to the present invention for achieving another object comprises the steps of: preparing a lower substrate and an upper substrate; preparing a mixture of a photo-dispersant and a reactive agent (RM) + photoinitiator; Coating the mixture on a substrate, performing soft baking and hard baking to form an optical polyimide layer, irradiating UV light of a first linearly polarized wavelength band for photo alignment, aligning the aligned substrates, And irradiating UV light of a second wavelength band to form a polymer network.

The mixture of the photo-dispersing agent and the reactive agent (RM) + photoinitiator is 95.7: 0.05: 4.2 wt%.

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

And a filter for passing or blocking a UV of a specific wavelength band in a UV irradiation step of any one of the wavelength bands during UV irradiation of the first and second wavelength bands.

In the step of forming the optical polyimide layer, the soft bake is performed at a temperature of 100 캜 for 2 minutes, and the hard bake is conducted at a temperature of 180 캜 for 1 hour.

According to another aspect of the present invention, there is provided an apparatus for manufacturing a liquid crystal display device capable of controlling a surface fixed energy according to the present invention includes a mixer for preparing a mixture of a photo-dispersant and a photoinitiator, A photo-alignment UV irradiating unit for irradiating linearly polarized ultraviolet light of a first wavelength band which reacts only with a photo-dispersing agent, aligning the aligned substrates, injecting liquid crystals, and a polymer network forming UV irradiating unit for irradiating UV in a second wavelength band in which the RM + photoinitiator reacts to form a polymer network.

The liquid crystal display device capable of controlling the surface fixed energy according to the present invention, the method of manufacturing the same, and the manufacturing apparatus therefor have the following effects.

First, it is possible to control the surface fixing energy by inducing polymerization and orientation of RM and RM by mixing UV (photo alignment) with RM (reactive mesogen).

Secondly, it induces the polymerization and polymerization of RM by only the UV wavelength, and it is possible to solve the problem caused by the dust and static electricity generated in the rubbing process.

Third, by using RM, it is possible to improve the response speed by increasing the weak surface fixing energy of the optical brightener, so that it can be applied to various liquid crystal display devices requiring high transmittance and fast response speed.

Fourth, by using UV curing agent and RM + photoinitiator which do not overlap the range of UV reaction wavelength, it is possible to form photo-alignment and polymer network by irradiating UV in response to each material.

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

Figs. 1 and 2 show a method of orienting a mixture of polyimide (PI) and RM on a substrate and a method of laminating PI and RM, respectively,
FIG. 3 is a cross-sectional view of a liquid crystal display device capable of controlling surface fixing energy according to the present invention
4A and 4B are diagrams showing a reaction state depending on the presence or absence of use of a UV filter
5 is a view showing a manufacturing process of a liquid crystal display according to the present invention,
6 is a flow chart of a process of manufacturing a liquid crystal display device capable of controlling surface fixing energy according to the present invention
7 is a cross-sectional view of a manufacturing process of a liquid crystal display device capable of controlling surface fixing energy according to the present invention
FIG. 8 is a block diagram of an apparatus for manufacturing a liquid crystal display device capable of controlling surface fixing energy according to the present invention

Hereinafter, preferred embodiments of a liquid crystal display device, a method of manufacturing the liquid crystal display device, and a manufacturing apparatus therefor according to the present invention will be described in detail.

The features and advantages of a liquid crystal display device, a method of manufacturing the same, and a manufacturing apparatus therefor according to the present invention will be apparent from the following detailed description of each embodiment.

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

FIGS. 4A and 4B are views showing the reaction state depending on the use of the UV filter. FIG. 5 is a view illustrating a manufacturing process of the liquid crystal display according to the present invention using UV selective irradiation.

The present invention is directed to a method of controlling the surface fixing energy by mixing a photo alignment and an RM (Reactive Mesogen) to induce orientation and RM polymerization reaction only at UV wavelength, And the photo-alignment and the polymer formation are carried out by irradiating UVs, which react with each material, using the wavelength ranges of which do not overlap.

The present invention enables simultaneous formation of photo-alignment and polymer network of RMs in one pixel using different wavelength bands of UV.

The structure and method for improving the surface fixing energy using the RM mixture and the RM mixture according to the present invention are not limited to any one specific liquid crystal mode, It is natural that the present invention can be applied to various liquid crystal modes depending on the characteristics of the liquid crystal (horizontal light distribution agent, vertical light distribution agent).

3, a liquid crystal display according to the present invention is formed by mixing a photo alignment, a reactive mesogen, and a photoinitiator on a first substrate 60 having a pattern electrode 50, A first surface fixed energy control mixed layer 40 in which light is magnified by UV irradiation in one wavelength band, a polymer network is formed by UV irradiation in a second wavelength band to control surface fixing energy, ) Is formed by mixing a photo alignment, a reactive mesogen (RM), and a photoinitiator on the first wavelength band, a light is magnified by UV irradiation in the first wavelength band, and a polymer network is formed by UV irradiation in the second wavelength band A second surface fixed energy control mixed layer 20 whose surface fixing energy is controlled and a liquid crystal layer 30 located between the first substrate 60 and the second substrate 10 facing each other.

The first surface fixed energy control mixed layer 40 and the second surface fixed energy control mixed layer 20 are formed by separating an appropriate wavelength band by using a UV light having a wavelength band different from that of the RM, To increase the surface fixing energy of the surface of the substrate.

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

Therefore, by first inducing photo-alignment with a UV exposure of 300 nm and forming a polymer network of RM through a UV exposure of 200 nm, it is possible to separate the UV reaction wavelength band of the photo-dispersing agent and the reactive mesogen (RM) The network formation is performed within one pixel.

The wavelength band is not limited to the above values. It is a matter of course that the UV reaction wavelength band of the photo-dispersing agent and the RM + photoinitiator can be widely varied depending on the material to be used.

FIGS. 4A and 4B are diagrams showing a reaction state depending on the use of a UV filter. FIG.

FIG. 4a shows the case of irradiation without discrimination of the UV wavelength band, and it is found that it is difficult to optimize the optical alignment and the formation of the polymer network due to a strong chemical reaction in both of the photo-dispersing agent and the reactive mesogen (RM) + photo initiator by UV light have.

On the other hand, in the case of using a UV filter for passing or blocking a UV in a specific wavelength band, as in the embodiment of the present invention, the UV light of the first wavelength band is optically magnified and the UV of the second wavelength band It can be seen that the polymer network is formed by the irradiation and the surface fixing energy is controlled.

The following is a description based on the physical properties of the material and the UV wavelength range to investigate the UV wavelength band in such a manner to proceed with the formation of a photo-alignment and a polymer network.

From the viewpoint of the physical properties of the material, it is possible to perform photo-alignment and polymer network formation by irradiating the reactive UV of each material when the ranges of the UV reaction wavelengths of the photo-dispersing agent and RM + photoinitiator used in the production do not overlap.

In an embodiment of the present invention, a photo-dispersing agent for irradiating UV in a high wavelength band and an RM + photoinitiator for irradiating UV in a somewhat lower wavelength band are used.

Here, in the case of RM, since the polymer network is formed with the help of a photoinitiator rather than by the UV itself, the UV wavelength band is selected considering the UV wavelength band of the photoinitiator in consideration of the reaction wavelength.

In terms of the range of UV wavelength, the UV wavelength is distributed in a wide range (250 nm to 450 nm), so that UV light having only a specific wavelength band can be selected and photo alignment and polymer formation can be performed even if the reaction wavelength band of the material overlaps.

For example, by using two different UV light sources having a narrow wavelength band, the UV wavelength band can be divided and examined to proceed with the formation of a photo-alignment and a polymer network. In the case of a UV light source of a wide wavelength band, Filters can be used for optical alignment and polymer network formation.

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

In addition to the use of filters, it is natural that UV wavelengths can be separated using other forms and methods.

5 is a view illustrating a manufacturing process of the liquid crystal display device according to the present invention using UV selective irradiation.

For the fabrication using UV selective irradiation, a layer of the material mixed with the photo-dispersing agent and RM + photoinitiator is spin-coated on the substrate, and the baking process is carried out at 180 ° C for 1 hour and 30 minutes.

A linear UV polarizer and a long pass filter for UV linear polarization are placed on the mixed material layer formed on the lower substrate and photo-alignment is performed by irradiating UV at 365 nm.

Subsequently, the lower substrate and the upper substrate are bonded to each other so as to face each other, and liquid crystal is injected thereinto. Then, UV irradiation at 254 nm is performed to increase the surface fixing 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.

FIG. 6 is a flowchart illustrating a manufacturing process of a liquid crystal display device capable of controlling a surface fixed energy according to the present invention, and FIG. 7 is a sectional view of a manufacturing process of a liquid crystal display device capable of surface fixed energy control according to the present invention.

In the following description, a liquid crystal display device having a pixel electrode line and a common electrode line is described as an example. However, the structure and method for improving the surface fixing energy using the RM mixture and the RM mixture according to the present invention are not limited to any particular liquid crystal mode But it is natural that it is applicable to various liquid crystal modes according to the characteristics of the light-emitting agent (horizontal light distribution agent, vertical light distribution agent) without limitation.

(S602), a lower substrate and an upper substrate having a pixel electrode line and a common electrode line are prepared (S601), and a mixture of a photo-dispersing agent + Reactive Meogen (RM) + photoinitiator (95.7:

Subsequently, the prepared mixture is coated on a substrate, followed by soft baking at a temperature of 100 DEG C for 2 minutes (S603). [

Then, hard baking is performed at a temperature of 180 DEG C for 1 hour to form an optical polyimide layer (S604)

Then, linearly polarized UV for photo alignment is irradiated (S605)

Here, the UV light to be irradiated irradiates the UV of the first wavelength band which reacts only with the light distribution agent.

As described above, the process of irradiating UV by separating the wavelength band can use the above-mentioned filter or selectively use the UV of the selected wavelength band according to the physical properties of the material.

Annealing is performed for five minutes at a temperature of 100 DEG C in order to increase the ordering of the injected liquid crystal. (S607)

Next, the UV in the wavelength band in which the RM + photoinitiator reacts is examined for forming the polymer network (S608).

The UV wavelength band, the baking temperature, the annealing temperature and the time to be irradiated in the manufacturing process of the liquid crystal display device are examples, and it goes without saying that the process can be performed differently depending on the physical properties of the material and the pattern design form.

A manufacturing apparatus for manufacturing a liquid crystal display device capable of controlling surface fixed energy according to the present invention will now be described.

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

The apparatus for manufacturing a liquid crystal display device according to the present invention may include a photo-alignment UV irradiator and a polymer network forming UV irradiator for irradiating UVs of different wavelength bands in order to separate the UV wavelength band, Respectively.

The composition is composed of a mixing treatment part 80 for preparing a mixture of light spreading agent + Reactive Meogen (RM) + photoinitiator (95.7: 0.05: 4.2 wt%) and a mixing treatment part 80 for coating the prepared mixture on the substrate, A baking treatment section 81 for performing soft baking for 1 hour at a temperature of 180 ° C and hard baking for 1 hour and a linearly polarized UV light of a first wavelength band reacting only with a photo- The photo-alignment UV irradiating unit 82 for irradiating the liquid crystal and the aligned two substrates are attached to each other and liquid crystal is injected and annealed at a temperature of 100 ° C for 5 minutes in order to increase the ordering of the injected liquid crystal A liquid crystal injection and annealing unit 83 and a polymer network forming UV irradiation unit 84 for irradiating UV in a second wavelength band in which RM + photoinitiator reacts to form a polymer network.

Here, the photoalignment UV irradiating unit 82 and the polymer network forming UV irradiating unit 84 are separated from each other. However, when the wavelength band is divided using a filter, the filter may be integrally formed.

The surface fixed energy control and the increase characteristics of the liquid crystal display according to the present invention manufactured using the above-described structure and manufacturing process are as follows.

To obtain 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, in general, a chiral dopant material is mixed in the liquid crystal, and when the chiral dopant is mixed, the twist angle of the liquid crystal can be described as a cell gap (d) / pitch (p) , For example, when d / p = 1, the twist angle at the corresponding cell gap is 360 °.

In the measurement according to the present invention, the d / p was measured at a d / p of 0.13 at a cell gap (d) of 3.2 and a pitch (p) of 24, where the twist angle was 48 °.

As the alignment angle of the upper and lower plates of the fabricated cell is 30 °, the liquid crystal having the power to return to 48 ° by the chiral dopant suppresses the bending force when the inner surface fixing energy is increased, The liquid crystal twist state can be maintained.

That is, it is possible to calculate the surface fixed energy by grasping how the twist angle is formed based on the alignment direction of the liquid crystal molecules by 30 °.

The calculation of the surface fixed energy is shown in Equation (1).

: 실제 꼬인 각 (=측정 된 Twist angle),

: 액정정렬 각 (=초기 배향각, 30°),

: 액정의 비틀림 상수(사용된 액정의 고유물성, 6 * 10^-12)이다.here,

: Actual twist angle (= measured Twist angle),

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

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

It can be seen from Table 1 that when the manufacturing process according to the present invention is applied by using the RM-mixed photopolymerization agent, it is possible to have a high surface fixing energy of about 16 times that of the conventional photo-alignment method .

The liquid crystal display device capable of controlling the surface fixed energy according to the present invention, the method of manufacturing the same, and the manufacturing apparatus therefor, can mix the photo alignment and the RM (Reactive Mesogen) And the surface fixation energy can be controlled by irradiating UV light to each material by using a material in which the range of UV reaction wavelengths of the photo-dispersing agent and the RM + photoinitiator do not overlap, thereby performing optical alignment and polymer formation.

As described above, it will be understood that the present invention is implemented in a modified form without departing from the essential characteristics of the present invention.

It is therefore to be understood that the specified embodiments are to be considered in an illustrative rather than a restrictive sense and that the scope of the invention is indicated by the appended claims rather than by the foregoing description and that all such differences falling within the scope of equivalents are intended to be embraced therein It should be interpreted.

10. Second substrate 20. Second surface fixed energy control mixed layer
30. Liquid crystal layer 40. First surface fixed energy control mixed layer
50. Pattern electrode 60. First substrate

Claims (10)

The first substrate is formed by mixing a photo-dispersing agent, a reactive mesogen (RM) and a photoinitiator. The first substrate is optically magnified by UV irradiation in the first wavelength band, and the polymer network is formed by UV irradiation in the second wavelength band, A first surface fixed energy control mixed layer whose fixed energy is controlled;
And a photoinitiator are mixed with a photo-dispersing agent, RM (Reactive Mesogen) and a photoinitiator on the second substrate, and a UV light of a first wavelength band is used for light distribution, and a polymer network is formed by UV irradiation of a second wavelength band, A second surface fixed energy control mixed layer whose fixed energy is controlled;
And a liquid crystal layer disposed between the first substrate and the second substrate facing 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 according to claim 1, wherein UV irradiation in a first wavelength band for photo-alignment and UV irradiation in a second wavelength band for forming a polymer network are performed in the same manner as UVs in a wavelength band of 250 nm to 450 nm, And a filter for passing or blocking UV in a specific wavelength band is laminated between the electrodes in the UV irradiation step. 2. The method of claim 1,

Lt; / RTI >
Where d is the cell gap, p is the pitch,

: Actual twisted angle,

: LCD alignment angle,

Is a twist constant of a liquid crystal. Preparing a lower substrate and an upper substrate;
Preparing a photocatalyst + RM (Reactive Meogen) + photoinitiator mixture;
Coating the mixture on a substrate, performing soft baking and hard baking to form an optical polyimide layer;
Irradiating a line polarized first wavelength band UV for light alignment;
Laminating aligned substrates and injecting and annealing liquid crystals;
And irradiating UV light of a second wavelength band to form a polymer network. ≪ RTI ID = 0.0 > 11. < / RTI > 6. The method of claim 5, wherein the mixture of the photoinitiator + RM (Reactive Meogen) + photoinitiator is 95.7: 0.05: 4.2 wt%. 6. The method according to claim 5, wherein the first wavelength band is 300 nm to 365 nm in which the photo-dispersing agent reacts, and the second wavelength band is 200 nm to 254 nm in which the RM (Reactive Meogen) + photoinitiator reacts. A method for manufacturing a liquid crystal display device. The method according to claim 5, characterized by further comprising the step of laminating a filter for passing or blocking UV of a specific wavelength band in the UV irradiation step of one wavelength band during UV irradiation of the first and second wavelength bands Wherein the liquid crystal display device has a surface fixed energy control. 6. The method according to claim 5, wherein in the step of forming the polyimide layer,
Wherein the soft baking is performed at a temperature of 100 캜 for 2 minutes and the hard baking is conducted at a temperature of 180 캜 for 1 hour. A mixing treatment section for preparing a photo-magnifying agent + RM (Reactive Meogen) + photoinitiator mixture;
A baking treatment unit for coating the mixture on a substrate, followed by soft baking and hard baking;
A photo-alignment UV irradiating unit for irradiating linearly polarized UV in a first wavelength band that reacts only with the photofinishing agent;
A liquid crystal injection and annealing unit for laminating aligned substrates and injecting liquid crystals, and annealing the substrates to enhance 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.

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