KR20080014429A - Imprint method - Google Patents

Abstract

An imprinting method is provided to improve the uniformity of the thickness of thin film pattern, thereby enhancing the velocity of post-process and quality. An imprinting method comprises the steps of coating a resin(3) on a substrate(1); placing a mold(5) on the resin and pseudo-curing the resin simultaneously with molding by using rollers(7,8) provided with a lamp(13); and irradiating UV rays to cure the resin. Preferably the resin is pseudo-cured whenever the internal roller penetration part(12) of the roller is superposed with the external roller penetration window(11); and the lamp is a UV lamp.

Description

Imprint method {IMPRINT METHOD}

1a to 1b are a perspective view and a cross-sectional view showing a roller according to the present invention.

Figure 2 is a perspective view showing the position of the imprint resin in the imprint process according to the present invention.

3A to 3B are perspective and cross-sectional views illustrating pressing and rolling the imprint mold during the imprint process.

4 is a perspective view showing an ultraviolet lamp for curing the resin during the imprint process.

5 is a perspective view showing a display panel according to the present invention;

<Description of the reference numerals for the main parts of the drawings>

1: substrate 3: resin

5: imprint mold 6: groove

7: outer roller 8: inner roller

9, 13: ultraviolet lamp 10: projection

11: transmission window 12: transmission part

15: blocking film 21: liquid crystal

23: upper alignment layer 25: common electrode

27: color filter 29: upper substrate

30: color filter substrate 31: black matrix

33: data line 35: pixel electrode

37 thin film transistor 39 gate line

41: lower substrate 43: lower alignment layer

45: thin film transistor substrate 47: column spacer

The present invention relates to an imprint method, and more particularly, to an imprint method capable of forming a uniform thin film pattern through an imprint process.

A liquid crystal display is a device that can display a desired image by adjusting the light transmittance of liquid crystal cells arranged in a matrix form according to image signal information. The liquid crystal display is a flat panel display device, which is thin and light, has a low power consumption and a low driving voltage, and is widely used in various electronic devices.

The liquid crystal display device has a liquid crystal display panel including a thin film transistor substrate and a color filter substrate, and a liquid crystal formed between the thin film transistor substrate and the color filter substrate. The liquid crystal display panel may be formed by using an imprint process instead of a photoresist process that requires a long process time and expensive equipment such as an exposure apparatus.

The imprint process includes a uniform front pressing method for pressing the imprint mold having a suitable shape according to the shape of the panel on the entire surface of the resin, a roller pressing method for bonding the imprint mold onto the resin and then pressing the roller with the imprint mold.

The roller pressurization method is to pressurize the imprint resin while the roller rotates at the same pressure and at the same speed from the pressurization start position of one side of the imprint mold to the pressurization end position of the other side of the imprint mold. It is then subjected to a curing process. However, if the process time between the imprint mold pressurization and the curing process is delayed, the imprint resin may appear in the form of a wave, and since the part after the roller has passed there is no pressurized area, the resin cannot remain pressurized. have.

Accordingly, a technical object of the present invention is to provide an imprint method of a display panel capable of forming a thin film pattern having a uniform thickness through an imprint process.

In order to achieve the above object, an imprinting apparatus and an imprinting method of a display panel according to the present invention comprise the steps of coating a resin on a substrate and at the same time molding the resin using a roller having a mold mounted on the resin and a lamp built-in Imprinting method comprising the step of temporarily curing and the step of curing the resin by irradiating ultraviolet rays.

Specifically, the resin is temporarily cured whenever the inner roller transmission part and the outer roller transmission window of the roller overlap. In addition, the inner roller transmission portion and the outer roller transmission window of the roller is characterized in that overlapping at the lower end of the roller.

On the other hand, the lamp is characterized in that the ultraviolet lamp.

Specifically, the resin is characterized in that the coating using any one selected from spin coating, slit coating and dispensing.

And, it is characterized in that the mold is placed in one end of the resin and sequentially contacted to the other end.

Other technical problems and advantages of the present invention in addition to the above technical problem will become apparent from the description of the preferred embodiment of the present invention with reference to the accompanying drawings.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

1 is a perspective view and a cross-sectional view showing a roller according to the present invention.

Referring to Figure 1, the roller is composed of an outer roller 7 and the inner roller (8).

The outer roller 7 is formed of an opaque material and has a structure including the transmission window 11.

The transmission window 11 is a place where ultraviolet rays are transmitted from the ultraviolet lamp 13 of the inner roller 8, and a transparent material such as glass or transparent acrylic is used.

The inner roller 8 is formed of a transparent material and is composed of a transmission part 12 between the ultraviolet lamp 13 and the blocking film 15 and the blocking film 15 through which the ultraviolet light passes.

The ultraviolet lamp 13 temporarily cures the resin through the transmission window 11 of the outer roller 7 during rolling.

The blocking film 15 is a material that does not transmit ultraviolet rays, except for the size corresponding to the transmission window 11, the inner portion of the blocking film 15 surrounds the inner roller 8. In addition, since the front part of the roller traveling direction should not be cured, the inner roller 8 is fixed and has a double structure in which only the outer roller 7 rotates. That is, the blocking film 15 is fixed to the inner roller 8 made of a transparent material, and the inner roller 8 is made of an opaque material so that only the outer roller 7 rotates. Thus, the ultraviolet light passes through the position where the transmission part 12 of the inner roller 8 part is located. As a result, the roller is rotated in the advancing direction and is temporarily hardened by transmitting ultraviolet rays only when the transmission part 12 of the inner roller 8 and the transmission window 11 of the outer roller 7 overlap. The part where the ultraviolet ray permeates and temporarily hardens becomes the lower end of the roller.

Performing an imprint process using the roller will be described with reference to FIGS. 2 to 5.

Figure 2 is an attempt to show the position of the imprint resin in the imprint process according to the present invention.

Referring to FIG. 2, a resin 3 is formed on a substrate 1 on which both surfaces are polished. As a specific coating method, a coating method such as spin coating, slit coating and dispensing is used. The resin 3 may also be used a liquid ultraviolet curable resin composition composed of an acrylate compound or the like reacting with ultraviolet rays, a sheet type ultraviolet curable resin composition composed of an epoxy resin, an unsaturated polyester resin, or the like.

3A and 3B are perspective and cross-sectional views illustrating pressing and rolling an imprint mold during an imprint process.

Referring to FIG. 3A, after the resin 3 is formed on the substrate 1, the rear end of the imprint mold 5 is aligned on one side of the resin 3. Rolling is carried out while the imprint mold 5 is sequentially brought into contact with the substrate 1 coated with the resin 3. If there is air between the imprint mold 5 and the resin 3, the part is detected as a defect, and when a soft mold is used, the contact is sequentially made from the edge of the substrate 1. As a result, the portion where the ultraviolet rays are irradiated through the transmission window 11 of the ultraviolet lamp 13 becomes the mold surface on which the roller presses the imprint mold 5. Therefore, the resin 3 located just below the mold surface is cured. The part where the resin 3 is temporarily hardened is irradiated with ultraviolet rays through the transmission window 11 of the outer roller 7, and then the outer roller 7 is rotated once and the transmission part of the transmission window 11 and the inner roller 8 is rotated. (12) is overlapped and it is a part to which ultraviolet-ray is irradiated again. Therefore, it can be seen that the resin 3 is temporarily cured at regular intervals.

Referring to FIG. 3B, the contacted part is rolled by arranging rollers in which a constant direction and speed and pressure are controlled by a roller controller. The pressing force is transmitted to the resin 3 by pressing the imprint mold 5 while moving from one side of the imprint mold 5, that is, from the pressing start position to the other end pressing position, thereby forming a thin film pattern. The thin film pattern is formed in the form of a pattern inverted and transferred to the contact portion by the resin 3 moving to the contact portion of the imprint mold 5. And the resin (3) remaining after being removed after pressing to maintain the original state. Thus, the contact portion in the form of a groove 6 is aligned with a region where a thin film pattern will be formed later.

Since the complete hardening time of the resin 3 currently used is about 15 second, it does not harden | cure completely enough to harden | cure a little while moving a roller. That is, it is not a problem at all in proceeding to the next step after temporary curing. In addition, it is possible to maintain a constant film thickness even after the roller advances.

4 is a perspective view showing an ultraviolet lamp for curing the resin during the imprint process.

Referring to FIG. 4, the imprint mold 5 uses a transparent polymer material through which ultraviolet rays can pass. An ultraviolet lamp 9 is placed on the imprint mold 5 to cure the pattern formed in the temporarily cured resin simultaneously with pressing through a roller on the substrate. The pattern formed here is cured through the ultraviolet rays of the ultraviolet lamp 9 passing through the imprint mold 5. And the imprint mold 5 surrounding the pattern which completed this hardening step is removed.

The rolling imprint process should go through the process of imprinting and curing the resin 3 after coating the resin 3. However, the alignment of the resin 3 and the imprint mold 5 or the shrinkage of the resin 3 may occur during this process. Therefore, the imprint mold 5 should maintain the pressurized state well. For this reason, the present invention employs a method in which the imprint process is temporarily cured after the resin 3 is temporarily cured together with the imprint mold 5 after the coating of the resin 3.

7 is a perspective view illustrating a display panel according to the present invention.

The liquid crystal display panel includes a thin film transistor substrate 45 and a color filter substrate 30 bonded to each other with a liquid crystal layer interposed therebetween.

The color filter substrate 30 includes a black matrix 31, a color filter 27, a common electrode 25, an upper alignment layer 23, and a column spacer 47 that are sequentially formed on the upper substrate 29.

The black matrix 31 divides the upper substrate 29 into a plurality of cell regions in which the color filter 27 is to be formed, and prevents light interference and external light reflection between adjacent cells. To this end, the black matrix 31 is formed on the lower substrate 41 to overlap at least one of the data line 33, the gate line 39, and the thin film transistor 37 formed on the upper substrate 29. .

The color filter 27 is formed to be divided into red (R), green (G), and blue (R) in the cell region divided by the black matrix 31 to transmit red, green, and blue light, respectively.

The common electrode 25 is a transparent conductive layer coated on the color filter 27 to supply a common voltage Vcom which is a reference when driving the liquid crystal 21.

The upper alignment layer 23 is applied for liquid crystal alignment on the upper substrate 29 on which the black matrix 31, the color filter 27, and the common electrode 25 are formed.

The column spacer 47 serves to maintain a constant cell gap between the thin film transistor substrate 45 and the color filter substrate 30. The column spacer 47 is formed of the same material as the upper alignment layer 23.

The thin film transistor substrate 45 includes a gate line 39 and a data line 33 formed on the upper substrate 29 to intersect with each other, and a thin film transistor 37 adjacent to an intersection thereof and a pixel formed in a pixel region formed in the intersection structure. An electrode 35 is provided.

The thin film transistor 37 allows the pixel signal supplied to the data line 33 to be charged and held in the pixel electrode 35 in response to the scan signal supplied to the gate line 39. To this end, the thin film transistor 37 may include a gate electrode connected to the gate line 39, a source electrode connected to the data line 33, a drain electrode positioned opposite to the source electrode and connected to the pixel electrode 35, and a source electrode. And an ohmic contact layer for ohmic contact with the active layer, the source electrode, and the drain electrode, which form a channel between the drain electrode and the drain electrode.

The pixel electrode 35 charges the pixel signal supplied from the thin film transistor 37 to generate a potential difference with the common electrode 25 formed on the color filter substrate 30. Due to the potential difference, the liquid crystal 21 positioned on the thin film transistor substrate 45 and the color filter substrate 30 is rotated by dielectric anisotropy, and the amount of light incident from the backlight unit via the pixel electrode 35 is adjusted. It is transmitted to the color filter substrate 30.

The lower alignment layer 43 is applied for liquid crystal alignment on the lower substrate 41 on which the thin film transistor 37 and the pixel electrode 35 are formed.

In the liquid crystal display panel according to the present invention, at least one of the upper alignment layer 23 and the lower alignment layer 43 and the column spacer 47 are simultaneously formed of the same material.

The alignment layer will be described by taking the upper alignment layer 23 formed on the upper substrate 29 as an example.

As shown in FIG. 2, the resin 3 is spin coated and slit coated on the upper substrate 29 on which the black matrix 31, the color filter 27, and the common electrode 25 are formed. And a coating method such as dispensing. Subsequently, the imprint mold 5 is aligned on the resin 3. The protrusion of the imprint mold 5 corresponds to the region where the upper alignment layer 23 is to be formed, and the groove of the imprint mold 5 corresponds to the region where the column spacer 47 is to be formed. The resin 3 is pressurized and temporarily hardened so that the surface of the protrusion of the imprint mold 5 and the resin 3 are connected. Accordingly, a portion of the resin 3 is moved into the groove of the imprint mold 5, so that the column spacer 47 of the pattern form inverted and transferred with the groove 6 of the imprint mold 5, and the protrusion of the imprint mold 5. An upper alignment layer 23 having a flat surface is formed in a region corresponding to 48.

Then, the imprint mold 5 and the resin 3 of the upper substrate 29 go through the curing step through the ultraviolet lamp 7.

In addition, the imprint method according to the present invention has been described with an example in which the upper alignment layer 23 and the column spacer 47 are simultaneously formed using the imprint mold 5. However, in addition to this, the lower alignment layer 43 and the column spacer 47 may be simultaneously formed using the imprint mold 5. As such, the imprint process may be used in all processes of making the display panel.

As described above, the imprint method according to the present invention may form a thin film pattern having a uniform thickness during the imprint process by temporarily curing the resin through an ultraviolet lamp located inside the roller after pressing the imprint mold. Accordingly, the progress of the subsequent process may be increased and the quality may be improved.

In the detailed description of the invention described above with reference to the preferred embodiment of the present invention, those skilled in the art or those skilled in the art having ordinary knowledge of the present invention described in the claims to be described later It will be understood that various modifications and variations can be made in the present invention without departing from the spirit and scope of the art.

Claims (6)

(a) coating a resin on a substrate; (b) placing the mold on the resin and temporarily curing the resin at the same time as the molding using a roller having a lamp; And (c) irradiating with ultraviolet light to cure the resin. The method of claim 1, And (b) the resin is temporarily cured whenever the inner roller transmission portion and the outer roller transmission window of the roller overlap. The method of claim 2, The inner roller transmission portion and the outer roller transmission window of the roller overlap at the lower end of the roller. The method of claim 1, And the lamp is an ultraviolet lamp. The method of claim 1, And the resin is coated using any one selected from spin coating, slit coating and dispensing. The method of claim 1, Imprint method, characterized in that the mold is placed in one end of the resin and sequentially contacted to the other end.

Images