JP2009198869A - Method for correcting defect of color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for correcting a defect of a color filter with which no new projection nor color mixing are produced on surrounding pixels even when a correction liquid is stuck to a correction opening produced by laser beam in correcting a pixel defect of the color filter. <P>SOLUTION: The method for correcting the defect of the color filter includes a process of providing the correction opening S2 by irradiating a defect part with laser beams, a process of providing a coating film 52 of a color correction liquid which is thinner than thickness of the pixel by sticking the color correction liquid to the correction opening, a process of curing the coating film, a process of sticking a transparent correction liquid onto the coating film to fill up and cover the correction opening and providing a coating film 53 of the transparent correction liquid so that sum of thickness of the coating film of the cured color correction liquid and thickness of the coating film of the transparent correction liquid after curing may be larger than thickness of the pixels surrounding the correction opening, a process of curing the coating film of the transparent correction liquid and a process of polishing a top surface of the coating film to make the top surface of the coating film of the transparent correction liquid equal to the top surfaces of the surrounding pixels. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a defect correction method for a color filter, and in particular, even if a correction liquid is applied to a correction port provided by irradiating a laser beam to a white defect or a black defect, the correction liquid is present around. The present invention relates to a method for correcting defects in a color filter that generates overlapping protrusions and that does not cause correction liquid to spread and color mixing.

In a display device, it is a useful means to use a color filter for purposes such as color display, reflectance reduction, contrast improvement, and spectral characteristic control.
In many cases, the color filter used in the display device is formed as a pixel. A photolithography method is widely used as a method of forming pixels of a color filter used in this display device.

FIG. 6 is a plan view schematically showing an example of a color filter used in the liquid crystal display device. FIG. 7 is a cross-sectional view taken along line XX ′ of the color filter shown in FIG.
As shown in FIGS. 6 and 7, in the color filter used in the liquid crystal display device, a black matrix (41), a colored pixel (42), and a transparent conductive film (43) are sequentially formed on a glass substrate (40). It has been done.
FIGS. 6 and 7 schematically show a color filter, and 12 colored pixels (42) are represented. In an actual color filter, for example, several hundreds are displayed on a 17-inch diagonal screen. A large number of colored pixels of about μm are arranged.

As a method of manufacturing a color filter having the above structure, which is used in many liquid crystal display devices, first, a black matrix is formed on a glass substrate, and then a colored pixel is aligned with this black matrix pattern. A method of forming a transparent conductive film and aligning a transparent conductive film is widely used.
The black matrix (41) is a matrix having light shielding properties, the colored pixels (42) have, for example, red, green, and blue filter functions, and the transparent conductive film (43) is transparent. Provided as a simple electrode.

  The black matrix (41) is composed of a matrix portion (41A) between the colored pixels (42) and a frame portion (41B) surrounding the peripheral portion of the region (display portion) where the colored pixels (42) are formed. Yes. The black matrix determines the position of the colored pixels of the color filter, makes the size uniform, and shields unwanted light when used in a display device, making the image of the display device uniform and uniform. In addition, it has a function of making an image with improved contrast.

  The black matrix is formed on the glass substrate by, for example, providing a coating film on the glass substrate (40) using a black photoresist for forming a black matrix, and exposing and developing the coating film to form a black matrix (41). ) Is used.

In addition, the colored pixel (42) is formed by providing a coating film on a glass substrate on which the black matrix is formed using, for example, a negative coloring photoresist in which a pigment or other pigment is dispersed. A method of forming colored pixels by exposure to light and development is used. In addition, the transparent conductive film (43) is formed on a glass substrate on which a black matrix and colored pixels are formed by, for example, forming a transparent conductive film by sputtering using ITO (Indium Tin Oxide). ing.
That is, a color filter used in a liquid crystal display device shown as an example is formed as a pixel (pattern) by a photolithography method except for a transparent conductive film.

When the black matrix (41) or the colored pixel (42) is formed, the pixel (pattern) may be defective. The pixel (pattern) defect is mainly classified into a white defect in which a part of the pixel is missing and a black defect due to adhesion of foreign matter.
The white defect is, for example, a pixel missing portion caused by flipping of the photoresist on the surface of the glass substrate, bubbles in the photoresist, peeling of the film due to removal of foreign matter on the pixel, or a portion where the thickness of the pixel is thin. That is, a pinhole. When a color filter having a pinhole is incorporated in a liquid crystal display device, it is viewed as a white spot, which impairs display quality.

Further, the black defect is a particle in which particles generated in the process, dust floating in the work place, and the like are attached, and the pixel is viewed darkly. This black defect often becomes a protrusion on the pixel. If the height of the protrusion is in contact with the counter substrate of the liquid crystal display device, a short circuit occurs and the display quality is deteriorated.
Accordingly, correction is applied to pixel (pattern) defects such as white defects and black defects generated when the black matrix (41) or the colored pixels (42) are formed.

1A to 1D are explanatory diagrams of an example of a method for correcting a white defect (pinhole). This correction method is a correction method for correcting a white defect by applying a correction liquid to the white defect portion.
FIG. 1A shows a state in which white defects (D1) are generated in the colored pixels (42) when the black matrix (41) and the colored pixels (42) are sequentially formed on the glass substrate (40). It is a representation. The size (a × b) of the colored pixel (42) is about 300 μm × 100 μm, and the film thickness is about 1.0 μm. The white defect (D1) having a size (c) of about 20 μm to 70 μm is to be corrected.

  FIG. 1B shows a stage in which the correction opening (S1) is formed in the white defect (D1) portion of the colored pixel (42). Since the planar shape of the white defect (D1) is indefinite, a simple shape, for example, a square shape around the white defect (D1) as shown in FIG. This is one in which colored pixels are removed. For removal of the colored pixels, for example, the portion is volatilized using a laser.

  FIG. 1C shows a stage where the correction port (S1) in the colored pixel (42) has been corrected and the correction film (45) has been formed. Moreover, FIG.1 (d) is sectional drawing in the XX line in FIG.1 (c). For the correction port (S1), the correction liquid is attached to the tip of the correction needle whose tip is processed flat, and the correction port (S1), that is, on the glass substrate surface exposed from the correction port (S1). Apply correction fluid.

As another method of depositing the correction liquid on the glass substrate surface, a method using a dispenser instead of the correction needle can be mentioned. This method is a correction method in which a correction liquid is filled in a glass dispenser, the correction liquid is discharged by pressurization with air, and the correction liquid is deposited on the correction port. For example, a small dispenser called a microdispenser having a main body inner diameter of about 1 mmφ and a discharge outlet inner diameter of about 5 to 10 μmφ is used.
According to the composition of the correction liquid, the correction liquid film on the glass substrate surface is cured by, for example, UV light irradiation or heat treatment using a spot heater to form a correction film (45), white defects Complete (pinhole) correction.

However, in the white defect correction method as described above, as shown in FIGS. 1C and 1D, the periphery of the corrected correction port (S1), that is, normal coloring that does not need to be corrected is used. Pixel (42
) May also be deposited on top of the other, and the correction liquid may overlap on the pixels around the correction opening (S1) to form a new protrusion (44).
This new protrusion (44) is likely to occur when the correction liquid has a high concentration. Further, when the correction liquid has a low concentration, it does not become a protrusion, and the correction liquid spreads on the pixels around the correction opening, and a new color mixture (defect) is likely to occur.
That is, this is a case where the defect correction operation is not performed well, and a new protrusion defect or a color mixing defect may occur, which is different from the white defect and black defect before correction.

Although the above describes the correction method of the white defect (D1) using the correction needle or the micro dispenser, the correction method of the black defect is the same. In the case of a black defect, the black defect (not shown), its lower layer, and surrounding colored pixels are volatilized by a laser, a correction port having a simple shaped shape is provided, and a correction liquid is applied and cured. .
JP 2001-166129 A JP 2004-67777 A

  The present invention has been made to solve the above problems, and corrects pixel (pattern) defects such as white defects and black defects in a color filter in which a black matrix and colored pixels are sequentially formed on a glass substrate. At this time, even if the correction liquid is deposited on the glass substrate surface exposed from the correction opening provided by volatilizing the corresponding part using laser light, the correction liquid overlaps on the pixels around the correction opening. It is an object of the present invention to provide a color filter defect correcting method that does not generate new protrusions, or that the correction liquid spreads on the pixels around the correction port and does not newly generate color mixing defects. It is.

The present invention provides a color filter defect correcting method in which a correction port is provided in a defective portion of a color filter formed on a glass substrate, and a correction liquid is applied to the correction port.
1) A step of irradiating a white defect or a black defect of the defective part with a laser beam to volatilize the corresponding part and its periphery, and providing a shaped correction port,
2) A step of depositing a color correction solution on a glass substrate surface exposed to the shaped correction port, and providing a coating film of the color correction solution having a thickness smaller than the thickness of the pixels around the correction port;
3) a step of curing the coating film of the color correction solution;
4) A transparent correction liquid is applied onto the cured color correction liquid coating, and the correction opening is filled and covered. The thickness of the cured color correction liquid coating and the coating after the transparent correction liquid is cured Providing a coating film of a transparent correction liquid so that the sum of the thicknesses of the films is thicker than the thickness of the pixels around the correction opening;
5) a step of curing the coating film of the transparent correction liquid;
6) Polishing the upper surface of the cured transparent correction liquid to make the upper surface of the cured transparent correction liquid flush with the upper surface of surrounding pixels.
A defect correction method for a color filter, comprising:

  According to another aspect of the present invention, there is provided a color filter defect correcting method according to the above-described invention, wherein a correction needle or a microdispenser is used to deposit the color correction liquid or the transparent correction liquid. .

  Further, the present invention is the color filter defect correction method according to the above invention, wherein the color correction solution coating or the transparent correction solution coating is cured by heating or UV light irradiation. This is a characteristic color filter defect correcting method.

  The present invention is also the color filter defect correcting method according to the invention, wherein the polishing is flat plate polishing or tape polishing.

  The present invention includes a step of providing a correction port shaped by irradiating a laser beam to a defective portion, and a color correction solution having a thickness smaller than the thickness of surrounding pixels by applying a color correction solution to the correction port. The step of providing, the step of curing the coating film of the color correction liquid, the transparent correction liquid is applied onto the cured film of the color correction liquid, the correction opening is filled and covered, and is thicker than the thickness of the pixels around the correction opening. The step of providing the coating film of the transparent correction liquid, the step of curing the coating film of the transparent correction liquid, polishing the upper surface of the cured transparent correction liquid film, and surrounding the upper surface of the cured transparent correction liquid coating The method of correcting a defect in a color filter comprising a step of making the top surface of the pixel flush with the upper surface of the pixel, so that when correcting the pixel defect in the color filter, the correction liquid is applied to the correction port provided using a laser beam. Even if it is done, the correction liquid will overlap on the surrounding pixels, generating new protrusions Or to also never or generating a new color mixing defect spread correction fluid on the surrounding pixels, the defect correction method of the color filter.

Hereinafter, the present invention will be described in detail based on embodiments.
2 to 5 are a partial plan view and a partial cross-sectional view of an example of a color filter for explaining a defect correction method for a color filter according to the present invention. FIG. 2 shows that white defects or black defects are generated in the colored pixels (42) formed on the glass substrate (40), and the white defects or black defects are irradiated with laser light. And the surrounding colored pixels (42) are volatilized, and a stage where a correction opening (S2) is provided is shown.

  2A is a plan view thereof, and FIG. 2B is a cross-sectional view taken along line XX of FIG. As shown in FIGS. 2A and 2B, the provided correction opening (S2) is an example in which an irregular defect is irradiated with laser light and shaped into a circle. The thickness (T1) of the colored pixel (42) is about 1 μm, and the diameter (D1) of the correction port (S2) is about 40 μm. The glass substrate (40) surface is exposed at the bottom of the correction opening (S2).

  FIGS. 3A and 3B show a stage in which a coating film (52) of the color correction solution is provided on the surface of the glass substrate (40) exposed at the bottom of the shaped correction port (S2). Is. The thickness (T2) of the coating film (52) is thinner (T2 <T1) than the thickness (T1) of the colored pixel (42) around the correction opening (S2). The amount of the color correction liquid that does not overflow from the correction port (S2), for example, the thickness (T2) of the coating film (52) is half the thickness (T1) of the colored pixel (42). Deposit the amount.

As a result, the color correction liquid is not overlapped on the colored pixels (42) around the correction port (S2) and new protrusions are not formed, and the color correction liquid spreads on the colored pixels (42) and is newly added. There is no color mixing.
A correction needle or a microdispenser can be used to adhere the color correction liquid to the correction port (S2).

The color density of the color correction solution is a color density that is comparable to the color density of the colored pixel (42) even if the thickness (T2) of the coating film is smaller than the thickness (T1) of the colored pixel. Keep it adjusted.
The amount of the color correction liquid deposited on the correction port (S2) is the same as or slightly higher than the color density of the surrounding colored pixels (42) in a state where the coating film of the color correction liquid is cured. preferable.

  Table 1 shows an example of the composition of the color correction solution. In this example, the color correction solution is cured by irradiation with UV light, but the color correction solution may be cured by heating. In that case, for example, a spot heater is used as a heat source.

図４（ａ）、（ｂ）は、カラー修正液の塗膜を硬化した後、修正口（Ｓ２）内のカラー修正液の塗膜（５２）上に、透明修正液の塗膜（５３）が設けられた段階を示したものである。表２は、透明修正液の組成の例を示したものである。この例はＵＶ光の照射によって硬化する透明修正液であるが、透明修正液としては、加熱によって硬化するするものでもよい。その際には熱源として、例えば、スポットヒーターが用いられる。透明修正液は無色であることが好ましい。

4 (a) and 4 (b) show a coating film (53) of the transparent correction liquid on the color correction liquid film (52) in the correction port (S2) after the color correction liquid coating film is cured. The stage in which is provided is shown. Table 2 shows an example of the composition of the transparent correction liquid. In this example, the transparent correction liquid is cured by irradiation with UV light, but the transparent correction liquid may be cured by heating. In that case, for example, a spot heater is used as a heat source. The clear correction fluid is preferably colorless.

透明修正液は、修正口（Ｓ２）内を充填し、更に修正口（Ｓ２）上、及び修正口（Ｓ２）の周囲の着色画素（４２）上を被覆するように被着する。透明修正液の塗膜（５３）の厚さは、硬化したカラー修正液の塗膜（５２）の厚さ（Ｔ２）と、透明修正液の塗膜（５３）の硬化後の厚さ（Ｔ３）の和（Ｔ４）が、周囲の着色画素（４２）の膜厚（Ｔ１）より厚くなる（Ｔ４＞Ｔ１）ように、透明修正液の塗膜（５３）の厚さを設ける。
上記のように、硬化した透明修正液の塗膜（５３）の上面の厚さ（Ｔ４）は、着色画素（４２）の膜厚（Ｔ１）より厚いものとし、また、透明修正液の塗膜（５３）の直径（Ｄ２）は修正口（Ｓ２）の直径（Ｄ１）より大きなものとする（Ｄ２＞Ｄ１）。

The transparent correction liquid fills the correction port (S2), and is further deposited so as to cover the correction port (S2) and the colored pixels (42) around the correction port (S2). The thickness of the coating film (53) of the transparent correction liquid is the thickness (T2) of the cured color correction liquid coating film (52) and the thickness after the curing of the transparent correction liquid coating film (53) (T3). ) Is thicker than the film thickness (T1) of the surrounding colored pixels (42) (T4> T1).
As described above, the thickness (T4) of the upper surface of the cured transparent correction liquid coating film (53) is larger than the film thickness (T1) of the colored pixel (42), and the transparent correction liquid coating film The diameter (D2) of (53) is larger than the diameter (D1) of the correction port (S2) (D2> D1).

5 (a) and 5 (b), after the coating film of the transparent correction liquid is cured, the upper surface of the cured coating film is polished, and the upper surface of the coating film (53) of the transparent correction liquid and surrounding colored pixels (42) are shown. ) Shows the stage where the upper surface is flush with the upper surface (M). For this polishing, flat plate polishing, tape polishing or the like can be used. By appropriately adjusting the height of the convex portion from the upper surface of the colored pixel generated in the coating film of the transparent correction liquid, it is possible to prevent the colored pixels around the defective portion from being damaged during polishing.
As shown in FIGS. 5A and 5B, the correction port (S2) is filled with a color correction solution coating film (52) and a transparent correction solution coating film (53), and the correction port (S2). There are no protrusion defects or color mixing defects due to the correction work on the colored pixels (42) around the.

Further, since the color density of the coating film (52) of the color correction liquid in the correction opening (S2) is substantially the same as the color density of the surrounding colored pixels (42), the difference is not identified and displayed. Quality is not impaired.
Furthermore, since the upper surface of the coating film (53) of the transparent correction liquid and the upper surface of the surrounding colored pixels (42) are flush with each other, the liquid crystal alignment is not hindered.

(A)-(d) is explanatory drawing of an example of the method of correcting a white defect (pinhole). In the example of the color filter for explaining the defect correcting method of the color filter according to the present invention, the stage where the correction port is provided is shown. (A), (b) shows the stage in which the coating film of the color correction liquid was provided on the glass substrate surface exposed at the bottom of the correction port. (A), (b) shows the stage in which the coating film of the transparent correction liquid was provided on the coating film of the color correction liquid in the correction mouth. (A), (b) shows the stage which grind | polished the hardened coating-film upper surface, and the coating-film upper surface of the transparent correction liquid and the surrounding coloring pixel upper surface were flush | leveled. It is the top view which showed typically an example of the color filter used for a liquid crystal display device. It is sectional drawing in the X-X 'line | wire of the color filter shown in FIG.

Explanation of symbols

40 ... Glass substrate 41 ... Black matrix 42 ... Colored pixel 43 ... Transparent conductive film 44 ... Protrusion 52 ... Color correction solution coating 53 ... Transparent correction solution coating D1 ... white defect S1, S2 ... correction opening

Claims (4)

In the defect correction method of the color filter, in which a correction port is provided in the defect portion of the color filter formed on the glass substrate, and the correction liquid is deposited on the correction port.
1) A step of irradiating a white defect or a black defect of the defective part with a laser beam to volatilize the corresponding part and its periphery, and providing a shaped correction port,
2) A step of depositing a color correction solution on a glass substrate surface exposed to the shaped correction port, and providing a coating film of the color correction solution having a thickness smaller than the thickness of the pixels around the correction port;
3) a step of curing the coating film of the color correction solution;
4) A transparent correction liquid is applied onto the cured color correction liquid coating, and the correction opening is filled and covered. The thickness of the cured color correction liquid coating and the coating after the transparent correction liquid is cured Providing a coating film of a transparent correction liquid so that the sum of the thicknesses of the films is thicker than the thickness of the pixels around the correction opening;
5) a step of curing the coating film of the transparent correction liquid;
6) Polishing the upper surface of the cured transparent correction liquid to make the upper surface of the cured transparent correction liquid flush with the upper surface of surrounding pixels.
A defect correction method for a color filter, comprising:   2. The color filter defect correcting method according to claim 1, wherein a correction needle or a micro dispenser is used to deposit the color correction liquid or the transparent correction liquid.   The color filter defect correction according to claim 1 or 2, wherein the color correction solution coating or the transparent correction solution coating is cured by heating or UV light irradiation. Method.   The defect correction method for a color filter according to claim 1, wherein the polishing is flat plate polishing or tape polishing.

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