KR20010035824A - Spraying apparatus of alignment layer for liquid crystal display panel - Google Patents

Abstract

PURPOSE: An alignment layer coating device for a liquid crystal display panel is provided to reduce the drying time of polyimide solution during the alignment process and minimize the inclusion of foreign substance. CONSTITUTION: An alignment layer forming method using an alignment coating device(20) comprises the following steps. Firstly, a substrate(200) is mounted on the upper of a plate(29) and solution(22) is loaded in the first roller(23) through a nozzle part(21a) from a dispenser(21) for storing polyimide solution(22). The first roller(23) rotates in one direction and the solution(22) is coated on the roller(23) uniformly. The solution(22) is transferred in the second roller(25) engaging with the first roller(23) and polyimide resin plate(26) attached to the second roller(25), and the rotating second roller(25) forms the solution with a fixed thickness on the substrate(200). The first cover plate(27) and the second cover plate(28) are mounted in the outer peripheral surfaces of the first roller(23) and the second roller(25), respectively. The cover plates(27,28) prevent the inclusion of foreign substance from the outside during the forming of an alignment layer. When a hot plate(210) mounted in the lower of the plate(29) with the substrate(200) receives heat from a heating part(230), the heat is transmitted to the substrate(200) through the plate(29). Therefore, it is possible to reduce the dry time of the alignment layer and secure the uniformity of thickness of the alignment layer.

Description

Spraying apparatus of alignment layer for liquid crystal display panel

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display panel, and more particularly, to an alignment film coating apparatus for a liquid crystal display panel whose structure is improved so as to improve uniformity during coating of the alignment film.

Liquid crystal display panel (LCD) is a display device that displays an image by injecting a liquid crystal having an intermediate property between a solid and a liquid between two thin glass substrates and generating contrast by changing the arrangement of liquid crystal molecules when power is supplied. In order to drive the screen, a light source for irradiating the liquid crystal phase is required.

The liquid crystal display panel may be classified into a transmissive type and a reflective type according to the light source to be irradiated.

The transmissive liquid crystal display panel irradiates a liquid crystal phase using a backlight, and includes a polarizing plate, a glass substrate, a transparent electrode, an alignment layer, a spacer, a color filter, and a light source device.

On the other hand, the reflective liquid crystal display panel reflects external light and implements an image, and includes a scattering reflector. When a voltage is applied, horizontally twisted liquid crystal layers are vertically aligned to pass light, and light is reflected by a reflector to implement a screen.

In such a liquid crystal display panel, the alignment layer plays a most important role in maintaining the liquid crystal molecules in a constant direction and acting as a display device through a continuous arrangement. Since it is difficult to obtain a desired molecular arrangement through the substrate simply, the liquid crystal material forms an alignment vector using an alignment film using a polymer compound.

In fact, the electromagnetic response of the liquid crystal has a slight inclination angle when the alignment layer and the liquid crystal molecules are bonded because the optical property is poor because the direction mobility is symmetrical when the director and the thickness direction n of the liquid crystal are vertical or horizontal. many. The azimuth angle representing the vector difference between the surface direction of the substrate and the thickness direction of the liquid crystal molecules is called a pre-tilt angle. The azimuth angle is divided into three directions, a horizontal direction, a parallel direction, a vertical orientation, and an inclined orientation, depending on the azimuth angle. .

In order to form such an alignment film on a substrate, the alignment agent solution is dropped on a rotating roller, and then the doctor blade is uniformly applied in contact with the outer peripheral surface of the roller. Subsequently, the roller on which the alignment agent solution is dropped is transferred to the solution while rotating in engagement with a printing roller having a polyimide resin plate, and the printing roller forms an alignment film on a substrate mounted on the plate. Next, the alignment of the liquid crystal is performed by silicon oxide (SiO) evaporation or rubbing.

Here, when the time for forming the alignment film becomes longer, the solvent contained in the alignment agent solution may be volatilized between the two rollers, thereby causing variation in the thickness of the alignment film. Also, since a plurality of rollers are exposed to the outside, foreign matter Occasionally, a pin hole occurs on the substrate.

In addition, unevenness in the thickness of the alignment film may be caused for the aforementioned reasons. When this phenomenon occurs, variations in voltage application in the liquid crystal layer occur in the liquid crystal display panel.

The present invention was devised to solve the above problems, and provides an alignment film coating apparatus for a liquid crystal display panel having an improved structure to reduce the drying time of the alignment agent solution when forming the alignment film on the substrate and to minimize the incorporation of foreign substances. Its purpose is to.

1 is a partially cutaway perspective view of a conventional liquid crystal display panel,

2 is a perspective view showing an alignment film applying apparatus according to a first embodiment of the present invention;

3 is a perspective view showing an alignment film applying apparatus according to a second embodiment of the present invention.

<Brief description of symbols for the main parts of the drawings>

10 ... Liquid Crystal Display Panel 11,12 ... Substrate

13,14 ... transparent electrode 15,16 ... alignment film

17.Liquid crystal 19,100 ... Polarizing plate

21,31 ... Dispensing 22,32 ... Orientation Solution

23,33 ... 1st roller 24,34 ... Doctor blade

25,35 ... 2nd roller 26,36 ... resin plate

27 ... 1st cover plate 28 ... 2nd cover plate

29 Plate 37 Cover plate

200,300 ... substrate 210,310 ... hotplate

220.Heating part

In order to achieve the above object, the alignment film coating apparatus for a liquid crystal display panel according to an aspect of the present invention,

A first roller in which the solution is dropped from the nozzle portion of the dispense for storing the alignment film solution;

A doctor blade installed on one side of the first roller in a direction of the rotation axis of the roller to uniformly apply the solution to the outer circumferential surface of the roller;

A second roller which meshes with the first roller and rotates and is attached to an outer circumferential surface of the resin plate to which the solution is transferred;

A plate on which a substrate on which an alignment film transferred from the resin plate is formed is mounted;

A cover plate installed on an outer circumferential surface of the at least one roller to prevent foreign matter from being mixed; And

And heating means installed on the plate side to heat it.

In addition, the cover plate is installed to be spaced apart from the outer peripheral surface of the rollers by a predetermined interval, characterized in that formed to surround them in the direction of the rotation axis of the rollers with a predetermined curvature.

In addition, the cover plate is formed with a predetermined curvature spaced apart from the second roller by a predetermined interval, it characterized in that it is formed so as to completely cover the area where the resin plate is formed.

Furthermore, the cover plate is formed integrally with the first cover plate surrounding the first roller, and the second cover plate surrounding the second roller to be spaced apart from the rollers by a predetermined interval in the direction of the rotation axis It is characterized by wrapping.

In addition, the heating means is characterized in that it comprises a hot plate installed in the lower portion to the plate to conduct heat, and a heating unit for applying a predetermined heat to the hot plate.

Hereinafter, an alignment film applying apparatus for a liquid crystal display panel according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 1, the transmissive liquid crystal display panel 10 includes a transparent front substrate 11 and a rear substrate 12. The first and second transparent electrodes 13 and 2, which are supported by the substrates 11 and 12 and are driven by the substrates 11 and 12, are opposite to the front and rear substrates 11 and 12. The electrodes 14 are formed in a shape perpendicular to each other.

The first liquid crystal alignment layer 15 and the second liquid crystal alignment layer 16 are formed on the first and second transparent electrodes 13 and 14 to form liquid crystal molecules in a predetermined direction. The liquid crystal layer 17 is formed between the first and second liquid crystal alignment layers 15 and 16. Spacers 18 are provided around the liquid crystal layer 17 to maintain a constant cell spacing.

On the other hand, the outer surface of the front and rear substrates (11, 12) is provided with a first polarizing plate 19 and a second polarizing plate 100 for controlling the input and output of light passing through the liquid crystal (17). In addition, in order to implement a color image of the liquid crystal display panel 10, a color filter 110 including red, green, and blue filters is interposed on the lower surface of the front substrate 11, and on the rear surface of the panel 10. As indicated by the arrow, a light source device (not shown) for projecting light is provided.

Here, the first and second alignment layers 15 and 16 may be formed using a separate coating device.

2 shows a first embodiment of an apparatus 20 for applying such an alignment film.

Referring to the drawings, the apparatus 20 is provided with a first roller 23 in which the solution 22 is dropped from the nozzle portion 21a of the dispense 21 storing the alignment agent solution. The first roller 23 is rotatable in one direction.

On one surface of the first roller 23, a doctor blade 24 is installed to uniformly apply the dropped solution 22 to the surface of the first roller 23 along the rotation axis direction. The end 24a of the rate 24 is in contact with the surface of the first roller 23.

The first roller 23 is engaged with the second roller 25 to which the loaded solution 22 is transferred. The second roller 25 is rotatable with the first roller 23. A resin plate 26 made of polyimide is attached to the surface of the second roller 25 with a predetermined width. The solution 22 dropped on the resin plate 26 is transferred.

According to a feature of the present invention, when the solution 22 dropped from the first roller 23 to the second roller 25 is transferred, or when the alignment film solution 22 is transferred to the resin plate 26. In the first and second rollers 23 and 25 and the resin plate 26, shielding means are provided so that no foreign matter is interposed from the outside.

That is, the first cover plate 27 is installed on the outer circumferential surface of the first roller 23 to have the same curvature as the outer circumferential surface of the first roller 23 and to be spaced apart by a predetermined interval. The first cover plate 27 surrounds the first roller 23 when the first roller 23 rotates.

In addition, the outer circumferential surface of the second roller 25 has the same curvature as the outer circumferential surface of the roller 25 and the second cover plate 28 is installed to be spaced apart by a predetermined interval in the rotational axis direction, and the second cover plate 28 is It has the range which includes the area | region to which the resin plate 26 adhered completely.

In addition, the first cover plate 27 and the second cover plate 28 are preferably formed integrally, and may be made of a metal material or other material that does not corrode the alignment agent solution 22 made of an organic solvent. have.

Meanwhile, a plate 29 is disposed below the alignment film applying device 20, and a substrate 200 on which the alignment film is to be formed is mounted on the plate 29. On the side of the plate 29 is applied a heating means for applying a relatively low temperature heat so that the solution 22 is applied to the substrate 200 and then uniformly applied.

That is, a hot plate 210 made of a material having thermal conductivity is installed on the bottom surface of the plate 29. The hot plate 210 is electrically connected to a heating unit 220 composed of a circuit for heating the hot plate 210.

Looking at the alignment film forming process using the alignment film applying apparatus 20 according to the first embodiment of the present invention having the above configuration as follows.

First, the substrate 200 on which the alignment layer is to be formed is mounted on the upper surface of the plate 29. Next, the solution 22 is dripped at the 1st roller 23 from the dispenser 21 which stores the aligning agent solution 22 through the nozzle part 21a.

The first roller 23 rotates in one direction, and the end portion 22a of the doctor blade 24 provided on the rear surface of the roller 23 contacts the outer circumferential surface of the roller 23 so as to contact the solution 22. It is apply | coated on the roller 23 uniformly.

Next, the solution 22 is transferred to the second roller 25 which is rotatably engaged with the first roller 23. The solution 22 is transferred to the polyimide resin plate 26 attached to the second roller 25, and the second roller 25 is rotated so that the solution 22 is placed on the substrate 200. It will be formed to a thickness of.

At this time, the first cover plate 27 and the second cover plate 28 are provided to be spaced apart from the outer peripheral surface of the first roller 23 and the second roller 25 by a predetermined interval. Due to the installation of the first and second cover plates 27 and 28, it is possible to prevent incorporation of foreign substances from the outside when the alignment layer is formed.

Meanwhile, in order to uniformly form the alignment layer on the substrate 200, thermal diffusion is attempted by applying relatively low temperature heat. That is, when the hot plate 210 installed under the plate 29 on which the substrate 200 is mounted receives heat from the heating unit 230, the heat is transferred to the substrate 200 through the plate 29. By transferring, the drying time of the alignment film can be reduced, and the uniformity of the film thickness can be ensured.

3 shows a second embodiment of the device 30 for applying the alignment film according to the second embodiment of the present invention.

Here, since it has a structure similar to the apparatus 20 shown in FIG. 2, only the main part according to the characteristics of the present invention will be described.

Referring to the drawings, the solution 32 dropped from the nozzle portion 31a of the dispense 31 is applied to the outer circumferential surface of the first roller 33, and the doctor blade installed on one side of the first roller 33 ( It is possible for the end 34a of 34 to contact the outer circumferential surface of the roller 33 so that the roller 33 can be uniformly applied during rotation.

The first roller 33 is engaged with the second roller 35 to transfer the solution 32, and the polyimide resin plate 36 to which the solution 32 is transferred to the outer circumferential surface of the second roller 35. Is installed.

Here, the cover plate 37 is installed to be spaced apart from the outer circumferential surface of the second roller 35 by a predetermined interval. The cover plate 37 preferably has the same curvature as the outer circumferential surface of the second roller 35. In addition, the cover plate 37 has a size including the entire area of the resin plate 36 to form the solution 32 from the resin plate 36 on the substrate 300 mounted on the plate 39. It has a width.

On the other hand, the lower plate 39 is provided with a hot plate 310 which is a heating means that can be applied to the relatively low temperature heat to reduce the drying time when the alignment film is formed on the substrate 300.

As such, since the cover plate 37 surrounds the outer circumferential surface of the second roller 35, foreign matters may be prevented from being formed when the alignment layer is formed, and uniform coating may be performed on the substrate 300.

As described above, the alignment film coating apparatus for the liquid crystal display panel of the present invention can prevent the incorporation of foreign substances from the outside when the alignment film is formed on the substrate by providing a cover plate on the outer circumferential surface of the plurality of rollers for transferring the alignment agent solution. Uniform coating is possible.

In addition, by mounting a heating means such as a hot plate on the bottom of the plate on which the substrate is mounted, it is possible to quickly dry it when the alignment film is applied on the substrate, thereby preventing unevenness of the thickness of the alignment film.

Although the present invention has been described with reference to one embodiment shown in the drawings, this is merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Claims (5)

A first roller in which the solution is dropped from the nozzle portion of the dispense for storing the alignment film solution; A doctor blade installed on one side of the first roller in a direction of the rotation axis of the roller to uniformly apply the solution to the outer circumferential surface of the roller; A second roller which meshes with the first roller and rotates and is attached to an outer circumferential surface of the resin plate to which the solution is transferred; A plate on which a substrate on which an alignment film transferred from the resin plate is formed is mounted; A cover plate installed on an outer circumferential surface of the at least one roller to prevent foreign matter from being mixed; And And heating means installed on the plate side to heat it. The method of claim 1, The cover plate is installed so as to be spaced apart from the outer circumferential surface of the roller, a predetermined curvature, the alignment film coating apparatus for a liquid crystal display panel, characterized in that formed to surround them in the direction of the rotation axis of the roller. The method of claim 2, The cover plate is formed with a predetermined curvature spaced apart from the second roller by a predetermined interval, the alignment film coating apparatus for a liquid crystal display panel, characterized in that formed to completely surround the area where the resin plate is formed. The method of claim 2, The cover plate may be formed so that the first cover plate surrounding the first roller and the second cover plate surrounding the second roller are integrally formed to be spaced apart from the rollers so as to surround the first and second rollers in the rotation axis direction. The alignment film coating device for liquid crystal display panels characterized by the above-mentioned. The method of claim 1, And the heating means includes a hot plate disposed below the plate to conduct heat, and a heating unit applying a predetermined heat to the hot plate.