JP2000258617A - Color filter and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a short circuit between a color filter and a counter substrate without limiting the design of the counter substrate by removing a transparent conductive film around the top of a spacer or removing the transparent conductive film on the spacer top and around the top to form a filter. SOLUTION: A black matrix 2 is formed by using a black paste on a nonalkali glass 1. Then a blue color layer 3 is formed to fill the openings in the black matrix 2 while a blue color layer 4 is simultaneously formed at the position where a spacer is to be formed on the black matrix 2. Similarly, a red color layer and a green color layer are formed in the openings 5, 7 and on the positions 6, 8 where the space is to be formed of the black matrix 2, respectively. Then a transparent protective layer 9 is formed and further a transparent conductive film 10 is laminated. Then the color filter substrate is set on a stage of a YAG laser illumination device, and the transparent conductive film 10 around the spacer is irradiated with laser light to produce the region 11 where the transparent conductive film 10 is removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a color filter using irradiation of high energy light such as a laser.

[0002]

2. Description of the Related Art In a liquid crystal display device conventionally used, plastic beads, glass beads or glass fibers are generally provided between two substrates for a liquid crystal display device in order to maintain the thickness (cell gap) of a liquid crystal layer. It is used as a spacer between them. Since spacers such as plastic beads are scattered in an air flow, the positions of the spacers are not determined, and the spacers are also present in a display region (a light-transmitting portion in a screen excluding a light-shielding portion) on a liquid crystal display device substrate. There is a problem that the display quality of the liquid crystal display device is deteriorated due to the scattering and transmission of light by the spacer.

When dispersing spacers such as plastic beads, the spacers are not uniformly dispersed due to the influence of air currents or static electricity, and the spacers may aggregate. When the spacers are aggregated, the display quality of the aggregated portion is degraded, and there is a problem in accurate holding of the cell gap.

To solve this problem, Japanese Patent Laid-Open Publication No.
324, JP-A-63-824054, JP-A-4-939
24, Japanese Patent Application Laid-Open No. 5-196946 proposes that a structure in which two or three colored layers are superposed is used as a spacer.

[0005] Normally, since a transparent conductive film serving as a liquid crystal driving electrode is formed on the colored layer, the transparent conductive film is also formed on the spacer having the above-mentioned structure in which the colored layers are overlapped. When the spacer is abutted against the opposing substrate to secure a cell gap, since the transparent conductive film also exists on the spacer, in order to avoid a short circuit between the color filter and the opposing substrate, the position where the spacer is abutted is set. Special consideration is required for the design, such as disposing an insulating layer on the counter substrate. However, there is a strong demand for higher definition of the liquid crystal display element, and in some cases, there is a case in which the restriction on the design of disposing the insulating film at the portion where the spacer abuts becomes an obstacle.

To solve this problem, Japanese Patent Laid-Open No. 10-2823 discloses a color filter in which the transparent conductive film on the upper end surface of a spacer having a structure in which colored layers are superposed is removed to expose the colored layers.
No. 32 proposes this. As a method for removing the transparent conductive film on the upper end surface, photolithography using a photoresist and polishing removal are exemplified. However, photolithography requires a long process of resist coating, drying, exposure, development, etching, and resist stripping, and a spacer cannot be manufactured at low cost. Control of the spacer height is very important for precise control of the cell gap, but precise control of polishing removal is difficult. Particularly, when polishing a large substrate at once, it is very difficult to maintain the polishing accuracy. On the other hand, even when a large substrate is sequentially polished and removed while scanning using a polishing tape having a width of several centimeters, it is difficult to ensure the uniformity of the polishing amount in the substrate surface. In addition, the polishing time is increased and the cost is increased.

The structure in which a transparent conductive film is disposed on a spacer on which a colored layer is superimposed is a structure in which a transparent conductive film, which is a hard inorganic film, is disposed on a relatively soft layer. It is difficult to remove only the transparent conductive film on the top of the spacer with good selectivity.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a spacer having a structure in which colored layers are superimposed so that a precise cell gap can be maintained. An object of the present invention is to provide a method for manufacturing a color filter at a low cost.

[0009]

To solve the above-mentioned problems, the present invention has the following arrangement. (1) A colored layer composed of three primary colors, a plurality of spacers formed by laminating at least two layers of the colored layer composed of the three primary colors and a black matrix layer, and the colored layer and the spacer are covered on the substrate. A color filter comprising the formed transparent conductive film, wherein the transparent conductive film around the top of the spacer or the transparent conductive film around the top of the spacer and around the spacer is removed. (2) After forming a colored layer of three primary colors on a substrate and laminating at least two layers of the colored layer of the three primary colors and a black matrix layer to form a plurality of spacers, a transparent conductive film is formed. A method for producing a color filter, comprising laminating and then removing the top of the spacer and / or the transparent conductive film around the top by light irradiation. (3) The method for producing a color filter according to (2), wherein the light irradiation is laser light having a wavelength of 690 nm or more.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The substrate used for the color filter of the present invention is not particularly limited, and inorganic substrates such as quartz glass, borosilicate glass, aluminosilicate glass, and soda lime glass having a silica-coated surface. Glasses and organic plastic films or sheets are preferably used. An opaque substrate such as a metal plate can be used as a color filter of the reflection type liquid crystal display device.

A black matrix is provided on the transparent substrate as needed. The black matrix may be formed by over-coating a metal such as chromium or nickel, or an oxide thereof, or a colored film, but forming a resin black matrix composed of a resin and a light-shielding agent requires manufacturing costs and waste treatment. It is preferable from the viewpoint of cost. It is also preferable to use a resin black matrix from the viewpoint of securing the height of the spacer of the present invention. The resin used for the black matrix is not particularly limited, but a photosensitive or non-photosensitive material such as an epoxy resin, an acrylic resin, a urethane resin, a polyester resin, a polyimide resin, and a polyolefin resin is preferably used. Can be

The photosensitive resin used as the resin for the black matrix or the resin for the colored layer described later includes photodecomposable resins, photocrosslinkable resins, and photopolymerizable resins. A photosensitive composition, a photosensitive polyamic acid composition, or the like containing a monomer, oligomer, or polymer having the formula (I) and an initiator that generates radicals by ultraviolet rays is preferably used.

The non-photosensitive resin used as a resin for a black matrix or a resin for a colored layer described later includes:
Although those which can be developed with the above various polymers are preferably used, a resin having heat resistance that can withstand such heat in a film forming process of a transparent conductive layer and a manufacturing process of a liquid crystal display device is preferable, and A resin having resistance to an organic solvent used in a manufacturing process of a liquid crystal display device is preferable, and a polyimide resin is particularly preferable.

Here, the polyimide resin is not particularly limited, but usually a polyimide precursor having a structural unit represented by the following general formula [I] as a main component is heated or heated by an appropriate catalyst. Those imidized are preferably used.

[0015]

Embedded image

Here, n in the general formula (1) is 0 or 1 to 1.
Number 4 R ¹ is an acid component residue, and R ¹ is a trivalent or tetravalent organic group having at least two carbon atoms. From the viewpoint of heat resistance, R ¹ contains a cyclic hydrocarbon, an aromatic ring or an aromatic heterocyclic ring and has 3 to 30 carbon atoms.
A valent or tetravalent group is preferred. Examples of R ¹ include a phenyl group, a biphenyl group, a terphenyl group, a naphthalene group,
Examples include, but are not limited to, groups derived from a perylene group, diphenyl ether group, diphenylsulfone group, diphenylpropane group, benzophenone group, biphenyltrifluoropropane group, cyclobutyl group, cyclopentyl group, and the like.

R ² represents a divalent organic group having at least two carbon atoms. From the viewpoint of heat resistance, R ² is preferably a divalent group containing a cyclic hydrocarbon, an aromatic ring or an aromatic heterocyclic ring and having 6 to 30 carbon atoms. Examples of R ² include phenyl, biphenyl, terphenyl, naphthalene, perylene, diphenylether, diphenylsulfone, diphenylpropane, benzophenone, biphenyltrifluoropropane, diphenylmethane, cyclohexylmethane, and the like. Derived groups include, but are not limited to.
In the polymer having the structural unit represented by the general formula (1) as a main component, R ¹ and R ² may each be composed of one of these, or a copolymer composed of two or more of each. It may be. As a solvent constituting the paste, N-methyl-2-pyrrolidone, N, N-dimethylacetamide,
Amide polar solvents such as N, N-dimethylformamide,
A lactone polar solvent such as γ-butyrolactone is preferably used.

As the acrylic resin, about 3 to 5 kinds of alkyl acrylate or alkyl methacrylate such as acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, cyclic acrylate or methacrylate, hydroxyethyl acrylate or methacrylate are used. Is used and a resin polymerized to a molecular weight of about 5,000 to 200,000 is used. When the spacer contains an acrylic resin, the content of the acrylic resin in the components constituting the spacer is preferably 50% by weight or more, and more preferably 60% by weight or more. The material constituting the acrylic resin spacer is not limited to photosensitive or non-photosensitive, but a photosensitive material is preferably used from the viewpoint of fine processing of the spacer. In the case of a photosensitive resin, a composition comprising an acrylic resin, a photopolymerizable monomer, and a photopolymerization initiator is preferably used. As photopolymerizable monomers, bifunctional, trifunctional
There are functional and polyfunctional monomers.
6-hexanediol diacrylate, ethylene glycol diacrylate, neopentyl glycol diacrylate, triethylene glycol acrylate, etc., and trifunctional monomers such as trimethylolpropane triacrylate, pentaerythritol triacrylate, and tris (2-hydroxyethyl) isocyanate And polyfunctional monomers such as ditrimethylolpropane tetraacrylate, dipentaerythritol penta and hexaacrylate. As the photopolymerization initiator, benzophenone, thioxanthone, imidazole, triazine and the like are used alone or in combination.

As the light shielding agent for the black matrix, carbon black, titanium oxide, titanium oxynitride,
In addition to metal oxide powder such as iron tetroxide, metal sulfide powder, and metal powder, a mixture of pigments such as red, blue, and green can be used. Among them, carbon black is particularly preferable because of its excellent light shielding properties. Since carbon black having a good dispersion and a small particle size mainly exhibits a brownish color tone, it is preferable to mix a pigment of a complementary color to carbon black to obtain an achromatic color.

As a method for dispersing a light-shielding agent such as a pigment of a complementary color to carbon black or carbon black, for example, after mixing a light-shielding agent or a dispersing agent in a polyimide precursor solution, a three-roll Sand grinder,
There is a method of dispersing in a dispersing machine such as a ball mill, but the method is not particularly limited. In addition, various additives may be added for improving the dispersibility of carbon black, or for improving applicability and leveling property.

The resin black matrix is formed by applying a black paste on a transparent substrate, drying the paste, and then patterning. As a method of applying the black paste,
A dip method, a roll coater method, a spinner method, a die coating method, a wire bar coating method, or the like is suitably used. Thereafter, heat drying (semi-curing) is performed using an oven or a hot plate. The semi-cure conditions vary depending on the resin, solvent and paste applied amount, but are usually heated at 60 to 200 ° C. for 1 to 60 minutes.

In the black paste film thus obtained, after a photoresist film is formed thereon when the resin is a non-photosensitive resin, and when the resin is a photosensitive resin, Exposure and development are performed as it is or after forming an oxygen barrier film. If necessary, the positive type photoresist film or the oxygen blocking film is removed and dried by heating (this cure). These curing conditions are slightly different depending on the amount of the polyimide resin obtained from the precursor, but are generally heated at 200 to 300 ° C. for 1 to 60 minutes. In the case of acrylic resin, the curing conditions are:
Generally, heating is usually performed at 150 to 300 ° C. for 1 to 60 minutes. Through the above process, a black matrix is formed on the substrate.

In addition to the method of applying a black paste on a substrate, a resin black matrix may be formed by a method (transfer method) in which a black layer applied and semi-cured on another substrate is transferred by heating and pressing. .

The thickness of the resin black matrix is preferably 0.5 to 2.0 μm, more preferably 0.8 to 1.
5 μm. When the film thickness is smaller than 0.5 μm, it is difficult to form a spacer having a sufficient height when forming a spacer by laminating a resin layer on a resin black matrix. It is not preferable because it becomes insufficient. On the other hand, when the film thickness is greater than 2.0 μm, although the light-shielding property can be ensured, the flatness of the color filter is easily sacrificed, and a step is easily generated.

The light shielding property of the resin black matrix is O
It is represented by the D value (common logarithm of the reciprocal of the transmittance), and is preferably 1.6 or more, more preferably 2.0 or more, in order to improve the display quality of the liquid crystal display device.
The preferred range of the thickness of the resin black matrix has been described above, but the upper limit of the OD value should be determined in relation to this.

Usually, (2)
An opening of 0 to 200) μm × (20 to 300) μm is provided.
A plurality of primary color layers are arranged. That is,
One opening is covered with any one of the three primary color layers, and a plurality of color layers of each color are arranged.

The coloring layer of the color filter includes at least three layers of three primary colors, red (R), green (G), blue (B) or cyan (C), magenta (M), and yellow (Y). Each pixel is provided with one colored layer of any of these three colors.

As the coloring agent used in the coloring layer, organic pigments, inorganic pigments, dyes and the like can be suitably used, and various additives such as ultraviolet absorbers and dispersants may be added. . A wide range of dispersants such as surfactants, pigment intermediates, dye intermediates, and polymer dispersants are used. In addition, various additives may be added for improving coating properties and leveling properties.

Specific examples of the pigment are represented by a color index (CI) number. Pigment Red 9, 97, 122, 123, 144, 14 as a red pigment
9, 166, 168, 177, 180, 190, 19
2, 215, 216, 224 and the like, and as a green pigment, Pigment Green C.I. I. No. 7, 10, 36, 3
7, 38, 47 and the like, and as a blue pigment, Pigment Blue 15, 15: 1, 15: 2, 15: 3, 15: 4,
15: 6, 16, 17, 21, 22, 60, 64 and the like, and as a yellow pigment, Pigment Yellow 13, 17,
20, 24, 83, 86, 93, 94, 95, 109,
110, 117, 125, 137, 138, 139, 1
53, 154, 166, 173 and the like, and as violet pigments, Pigment Violet 19, 23, 29, 30, 3
2, 33, 36, 37, 38 and the like, and as an orange pigment, Pigment Orange 13, 31, 36, 38, 40, 4
2, 43, 51, 55, 59, 61, 64, 65, and the like; Pigment Blue 15, 16 and the like as indigo pigments; and Pigment Red 81 and 122 as red pigments.
144, 146, 169, 177, and Pigment Violet 19 can be employed. These pigments may be used alone or in combination of two or more. If necessary, the pigment may be subjected to a surface treatment such as a rosin treatment, an acidic group treatment, and a basic treatment.

The resin used for the colored layer is not particularly limited, but may be an epoxy resin, an acrylic resin, a urethane resin, a polyester resin, a polyimide resin,
A photosensitive or non-photosensitive material such as a polyolefin resin can be employed. Since the spacer of the present invention is preferably formed of a tough resin capable of performing fine processing and withstanding pressure, it is preferable to use an acrylic resin or a polyimide resin, and a polyimide resin is more preferably used. Can be

As a method for forming the colored layer, the same method as that for the black matrix can be employed. After applying and drying a paste containing a colorant on the substrate, patterning is performed. As a method of obtaining a colored paste by dispersing or dissolving the colorant, after mixing the resin and the colorant in a solvent,
There is a method of dispersing in a dispersing machine such as a three roll, sand grinder, ball mill and the like.

As a method for applying the colored paste, a dipping method, a roll coater method, a spinner method, a die coating method, a wire bar coating method, etc. are preferably used, as in the case of the black paste, and thereafter, an oven or hot Heat drying (semi-cure) is performed using a plate. The semi-curing conditions vary depending on the resin, solvent and paste applied amount, but are usually heated at 60 to 200 ° C. for 1 to 60 minutes.

In the colored paste film thus obtained, after a photoresist film is formed thereon when the resin is a non-photosensitive resin, and when the resin is a photosensitive resin, Exposure and development are performed as it is or after forming an oxygen barrier film. If necessary, the photoresist film or the oxygen barrier film is removed, and the film is dried by heating (this cure).

When the polyimide resin is obtained from the precursor, the curing conditions are slightly different depending on the coating amount.
Generally, heating is performed at 0 to 300 ° C. for 1 to 60 minutes.
In the case of acrylic resin, this curing condition is usually 15
Generally, heating is performed at 0 to 300 ° C. for 1 to 60 minutes.
Through the above process, a patterned colored layer is formed on the substrate. Further, the colored layer may be formed by a so-called transfer method.

After the first color layer is formed on the entire surface of the substrate as described above, unnecessary portions are removed by photolithography to form a desired pattern of the first color layer. . Repeat the same operation,
A color pattern of a color and a color pattern of a third color are formed.

In the present invention, the colored layer of the color filter is laminated simultaneously with the processing of the colored layer so that a separate step of forming a spacer on the color filter is not required, or in order to realize a spacer having a sufficient height. To form a spacer.

The spacer of the present invention is formed by laminating at least two layers of a colored layer having three primary colors and a black matrix layer. If the cell gap of the liquid crystal display element is relatively large, it is necessary to laminate all three primary color layers on the resin black matrix layer, while a liquid crystal display element using ferroelectric liquid crystal has a narrow cell of about 1 μm. Since a gap is used, it can be dealt with by laminating one colored layer on the resin black matrix layer or laminating two colored layers on the chrome black matrix layer. When a color superimposed black matrix in which two colored layers are superposed is employed, a spacer is formed in the third color on the color superimposed black matrix layer.

Along with the formation of the spacer, a laminate having a height that does not function as a spacer may be formed. For example, when the spacer is formed with four layers, the spacer is formed with three or less layers, and when the spacer is formed with three layers, 2 is formed.
It is formed of a laminate composed of layers. These do not normally come into contact with the opposing electrode substrate, but when the liquid crystal display device is pressurized, it comes into contact with the opposing electrode substrate to secure the cell gap and to ensure the reliability of the display quality of the liquid crystal display device. Can be enhanced.

The weight ratio between the resin component and the colorant component of the colored layer of the present invention is preferably 3: 7 to 9: 1 in that the spacer has a desired height and the color filter has a desired color display performance. It is preferable from the point of having.

The coloring layer on the opening and the coloring layer forming the spacer may be continuous or separated.

It is desirable that the spacer of the present invention is designed such that the area of the contact portion to the counter substrate is smaller than the area of the bottom of the spacer when the patterns are laminated.

The shape of the spacer of the present invention, that is, the cross-sectional shape when the spacer is cut along a plane parallel to the substrate is not particularly limited, but may be a circle, an ellipse, a polygon having rounded corners, a cross, a T-shape, or the like. An L-shape is preferred. In the case where a spacer is formed by laminating a plurality of color layers, the shape of the spacer in each layer is not particularly limited, but may be a circle, an ellipse, a polygon having rounded corners, a cross, a T-shape, or an L-shape. Preferably, these may be arbitrarily laminated to form a spacer.

The height of the spacer is preferably 2 to 9 μm, more preferably 3 to 8 μm. If the height of the spacer is lower than 2 μm, it is difficult to secure a sufficient cell gap. On the other hand, if the thickness exceeds 9 μm, the cell gap of the liquid crystal display device becomes too large, and the voltage required for driving becomes undesirably high. In addition, the height of the spacer refers to a single spacer, and means the distance between the opening coloring layer of the color filter and the uppermost surface of the spacer. When there is unevenness in the height of the display portion flat portion on the substrate, it indicates the largest one of the distances between the uppermost surface of the spacer and each display portion flat portion.

From the viewpoint of increasing the uniformity of the space between the two substrates for the liquid crystal display device held by the spacer in the screen,
Although it is preferable to form the spacer in the non-display area inside and outside the screen, the spacer may be formed in either the non-display area inside or outside the screen in some cases.

The area and location of each spacer are greatly affected by the structure of the liquid crystal display device. Constraints of the area of the non-display region 1 in the pixel in a color filter having a fixed spacer, the spacer area per one screen is preferably 10μm ² ~1000μm ^2. More preferably, 10 μm ^{2 to} 25
0 μm ² . The spacer area here is the top of the spacer formed on the color filter,
It refers to the area of a portion that comes into contact with a counter substrate or the area of a portion that comes into contact with a spacer formed on a counter substrate when a liquid crystal display device is manufactured. When the area of each spacer is smaller than 10 μm ² , it is difficult to form and laminate a precise pattern, and the spacer may be broken by pressure application during manufacturing of the liquid crystal display device. If the area of one spacer is larger than 1000 μm ² , it is difficult to perform a sufficient orientation treatment by rubbing around the spacer. Also, the spacer in the screen is
Although it depends on the shape of the spacer, it is difficult to completely dispose it in a non-display area in the screen. On the other hand, the spacer outside the screen does not appear in the display area. Therefore, in the case of a substrate for a liquid crystal display device having spacers in the plane and outside the screen, the area per spacer outside the screen is equal to the area per spacer inside the screen to facilitate formation of the spacers. Or larger. Spacers are provided outside the screen and also in a light-shielding portion that surrounds the screen called a frame. A transparent conductive film is also formed on and around part or all of the spacer in this portion. In the present invention, the transparent conductive film may be removed from the spacer on the frame. Instead of removing the transparent conductive film, it can be used as a power supply point from the counter substrate to the color filter substrate transparent conductive film.

Although the spacer of the present invention is formed on the color filter, a spacer is also formed on the counter substrate of the color filter at a position where the spacer abuts on the color filter. It is also possible to use the spacer with the spacer.

Further, in the color filter of the present invention, a transparent protective layer may be formed before forming the transparent conductive layer. The formation of such a transparent protective layer is disadvantageous in that the structure of the color filter is complicated and the production cost is high. It is advantageous.

After the formation of the three colored layers or the formation of the transparent protective layer, a transparent conductive film is formed. As the transparent conductive film, an oxide thin film such as ITO is adopted, and usually 0.1 μm
Although an ITO film of a certain degree is formed by a sputtering method, a vacuum evaporation method, or the like, the transparent conductive film is formed not only on the colored layer in the black matrix opening but also on the spacer. Further, the transparent conductive film on the colored layer and the transparent conductive film on the spacer are continuous and electrically conductive. The spacer is abutted against the opposing substrate to secure a cell gap. In order to avoid a short circuit between the transparent conductive film on the color filter and the pixel electrode or the wiring on the opposing substrate, special consideration is required, such as disposing an insulating film at a position where the opposing substrate abuts the spacer. In addition, the insulating film forming region must be larger than the area of the top of the spacer in consideration of the displacement at the time of bonding the substrates, which is a constraint on the liquid crystal display element design. In particular, the degree of restriction is large in a high-definition liquid crystal display device in which electrodes and wirings are densely arranged.

The method for producing a color filter of the present invention is characterized in that at least the top of the spacer and / or the transparent conductive film around the top are removed by light irradiation. Since the purpose of the present invention is to avoid a short circuit between the conductive film on the color filter and the counter substrate electrode or wiring, it is important to remove at least the top of the spacer and / or the transparent conductive film around the top. In order to reliably prevent a short circuit with the opposing substrate, it is preferable to remove not only the transparent conductive film at the top of the spacer but also the transparent conductive film around the top. Especially when pressure is applied to the liquid crystal display element
Since the spacer is compressed, it is preferable to remove the transparent conductive film in the peripheral portion of the top following the top.

Here, the periphery of the top of the spacer is a portion surrounding the highest point of the spacer, and includes a sloped portion of the spacer, a terrace-shaped portion surrounding the top if the spacer is formed in a multi-stage manner, and the spacer. The size can be selected within a range that does not disturb the display. On the other hand, by leaving the transparent conductive film on the top portion and removing the transparent conductive film around the top portion, that is, the inclined portion of the spacer, which is the peripheral portion of the top portion, so as to surround the top portion, the opposite conductive substrate can be removed. Short circuit can be avoided.

One form of the color filter provided by the present invention is a color filter in which the transparent conductive film is removed so as to surround the top of the spacer. In processing by laser light, it is possible to selectively remove the transparent conductive film due to the difference in light absorption coefficient between the transparent conductive film and the underlying colored layer, but the intensity of the laser light exceeds an appropriate range Then, the underlying colored layer is thermally deformed under the influence of heat generation of the transparent conductive film, and the shape (height) of the spacer changes. To avoid this, it is effective to remove the transparent conductive film so as to surround the top of the spacer. Also, as described above, when the liquid crystal display element is compressed, not only the top, but also
Since the top peripheral portion following the top may come into contact with the opposing substrate, the color filter from which the transparent conductive film is removed so as to surround the top is highly safe.

In particular, in applications where safety is emphasized, in addition to light irradiation, the transparent conductive film around the top portion or the transparent conductive film around the top portion and its surroundings may be removed by photolithography or the like.

The light for removing the transparent conductive film includes:
It is preferable that the transparent conductive film has a sufficient absorption coefficient while the colored layer has a small absorption coefficient. That is, the wavelength is preferably in a wavelength region of 690 nm or more, and more preferably 800 nm or more. On the other hand, if the wavelength is too long, it is not possible to irradiate light by focusing on a minute area. The wavelength is preferably 1/3 to 1/2 the size of the irradiation target. Therefore, as the light source, a YAG laser, a YLF laser, a ruby laser, a glass laser, an infrared semiconductor laser, a carbon dioxide laser, or the like is suitably employed. The wavelength of the YAG laser is 1064 nm, and the wavelength of the YLF laser is 1053 n.
m, ruby laser wavelength is 690 nm, glass laser wavelength is 1060 nm, carbon dioxide laser wavelength is 1
0600 nm. Examples of the wavelength of the high-output infrared semiconductor laser include a wavelength of 790 nm to 980 nm. Lasers include continuous-wave CW lasers and pulsed lasers. In the present invention, any laser can be used as long as a desired region can be heated. To irradiate and remove the upper transparent conductive film, a pulse laser is more easily applied. It is preferable to use a YAG laser in terms of light intensity and light intensity stability.

As a method of focusing light to remove the top of the spacer and / or the transparent conductive film around the top, there are the following methods.
There are a method of using an optical system such as a lens and a method of combining an optical system with a light shaping mask made of a metal plate or the like. In order to irradiate a predetermined position, there is a method in which a color filter is mounted on a stage and moved, or a laser beam is scanned by a galvanomirror or the like. Further, a method of irradiating light only to a predetermined position using an optical mask plate made of a metal plate or a dielectric thin film can also be adopted.

The light irradiation time is preferably longer in order to sufficiently heat and evaporate the transparent conductive film, and shorter in order to suppress damage to the colored layer and to increase the processing speed. Is preferable, the irradiation time per light is preferably in the range of 0.05 ns to 10 μs,
The range of 0.5 ns to 1 μs is more preferable. In addition, the irradiation light power density is preferably large in order to sufficiently heat and evaporate the transparent conductive film, and the irradiation light power density is preferably small in order to suppress damage to the colored layer,
Range of 0.5J / cm ² ~100J / cm ² is preferred.

The laser irradiation range of one shot is preferably equal to or larger than the size of the top of the spacer in order to increase the processing speed, while it is small in order to improve the uniformity of the irradiation light power density in one shot. Is more preferable.

When the transparent conductive film around the top of the spacer is removed while leaving the top of the spacer, the circumference of the top of the spacer is shot in one shot or more using an optical mask made of a metal plate or a dielectric thin film in order to increase the processing speed. It is preferable to be able to process with a small number of shots.

The color filter of the present invention and a method of manufacturing a liquid crystal display device using the same will be described below with reference to FIG. 1, but the present invention is not limited thereto.

An example of a method for manufacturing a color filter having a spacer will be described. A black matrix 2 is formed on a non-alkali glass 1 using a black paste. The blue coloring layer 3 was formed so as to fill the opening of the black matrix, and at the same time, the blue coloring layer 4 was disposed at the spacer forming position on the black matrix. Similarly, the red coloring layer is formed with the openings 5 and the spacer formation positions 6 of the black matrix, and then the green coloring layer is formed with the openings 7 and the spacer formation positions 8 of the black matrix. Next, a transparent protective layer 9 is formed, and a transparent conductive film 10 is further laminated.
Next, the color filter substrate was set on a stage of a YAG laser irradiation device provided with an XY stage, and the transparent conductive film around the spacer was irradiated with laser light to produce a portion 11 from which the transparent conductive film was removed. After removing the transparent conductive film, cleaning may be performed for the purpose of removing residues.

The color filter of the present invention and the method of manufacturing the same are also effective for a color filter on array in which a color filter is also formed on a so-called array substrate in which driving elements such as TFTs and signal wiring are arranged on the substrate.

The color filter of the present invention and a liquid crystal display device using the same are provided with a personal computer, a word processor,
It is used for display screens of engineering workstations, navigation systems, liquid crystal televisions and the like, and is also suitably used for liquid crystal projection and the like. Further, in the field of optical communication and optical information processing, it is suitably used as a spatial modulation element using a liquid crystal. A spatial modulation element modulates the intensity, phase, polarization direction, etc. of light incident on the element according to an input signal to the element, and is used for real-time holography, a spatial filter, incoherent / coherent conversion, and the like. It is.

[0062]

EXAMPLES Preparation Example 1 4.08 g of methyltrimethoxysilane, 9.9 g of phenyltrimethoxysilane and 28.8 g of γ-aminopropylmethyldiethoxysilane were prepared by adding 156.gamma.-butyrolactone.
3 g and 150 g of 3-methyl-3-methoxybutanol were dissolved, and 9.12 g of distilled water was added with stirring at 30 ° C., followed by heating and stirring at 50 ° C. for 2 hours to carry out hydrolysis and condensation. Then, the temperature was raised to 130 ° C., and the alcohol and water produced were distilled off while further condensing. After cooling this solution to 50 ° C., 3,3 ′, 4,4 with stirring
4'-benzophenonetetracarboxylic dianhydride 24.
17 g was added to obtain an amic acid-based polyorganosiloxane solution.

Preparation Example 2 272 g of methyltrimethoxysilane and 396 g of phenyltrimethoxysilane were dissolved in 785.6 g of 3-methyl-3-methoxybutanol, and then phosphoric acid was added to the solution while stirring.
A mixture of 34 g and 216 g of distilled water was added. The obtained solution was heated at 105 ° C. for 1 hour, and 302 g of a component mainly composed of methanol was distilled off. Then, the mixture was heated at 130 ° C. for 2 hours to obtain a component 147 mainly composed of alcohol and water.
g was distilled off. After cooling to room temperature, 86 g of 3-methyl-3-methoxybutanol was added to obtain a polyorganosiloxane solution.

Preparation Example 3 650 g of ethyl acetoacetate and 3-methyl-3-
383 g of tetrabutoxyzirconium was added to a mixed solution of 1567 g of methoxybutanol, and the mixture was stirred at 30 ° C. for 1 hour, and then left for 24 hours to obtain a zirconia chelate solution.

Example 1 (Preparation of resin black matrix) 3, 3 ', 4, 4'
-144.1 g of biphenyltetracarboxylic dianhydride was mixed with 1095 g of γ-butyrolactone and 209 g of N-methyl-2-pyrrolidone, and 95.1 g of 4,4′-diaminodiphenyl ether and bis (3-aminopropyl) tetramethyldimethyl Add 6.2 g of siloxane and add 3 at 70 ° C.
After reacting for 2 hours, 2.96 g of phthalic anhydride was added and further reacted at 70 ° C. for 1 hour to obtain a polyimide precursor (polyamic acid) solution.

A carbon black mill base having the following composition was mixed with a homogenizer at 7000 rpm for 3 hours.
The mixture was dispersed for 0 minutes, and the glass beads were filtered to prepare a black paste.

Carbon black mill base Carbon black (MA100, manufactured by Mitsubishi Chemical Corporation) 4.6 parts Polyimide precursor solution 24.0 parts N-methyl-2-pyrrolidone 61.4 parts Glass beads 90.0 parts 300 × 350 mm A black paste was applied on a non-alkali glass (OA-2, manufactured by NEC Corporation) substrate having a size of
For 20 minutes. Subsequently, a Posi-type photoresist ("Microposit" RC100 30 cp manufactured by Shipley Co., Ltd.) was applied by a spinner and dried at 80 ° C. for 210 minutes. The photoresist film thickness was 1.5 μm. Exposure was performed through a photomask using an exposure machine PLA-501F manufactured by Canon Inc.

Next, an aqueous solution containing 2% by weight of tetramethylammonium hydroxide at 23 ° C. was used as a developer.
The substrate was dipped in a developing solution, and simultaneously, the substrate was swung so as to make one reciprocation in a width of 10 cm in 5 seconds, thereby simultaneously developing the positive resist and etching the polyimide precursor. The development time was 60 seconds. Thereafter, the positive photoresist was peeled off with methyl cellosolve acetate, and further cured at 300 ° C. for 30 minutes to obtain a resin black matrix substrate. The thickness of the resin black matrix is
It was 1.2 μm and the OD value was 3.8. (Preparation of colored layer) Color in as red, green and blue pigments
dex No.65300 Pigment Red 177 dianthraquinone pigment, Color Index No.74265 Pigment Green 36
Color Inde, a phthalocyanine green pigment represented by
x A phthalocyanine blue pigment represented by No. 74160 Pigment Blue 15-4 was prepared. The pigments were mixed and dispersed in the polyimide precursor solution used for the black matrix to obtain three kinds of colored pastes of red, green and blue. First, a blue paste was applied on a resin black matrix substrate and semi-cured at 120 ° C. for 20 minutes. After this, a positive photoresist ("Microposit" RC100 3 manufactured by Shipley Co., Ltd.)
0cp) was applied with a spinner and dried at 80 ° C. for 20 minutes.
Exposure was performed using a photomask, and while the substrate was immersed and rocked in a 2% by weight aqueous solution of tetramethylammonium hydroxide, development of a positive type photoresist and etching of a polyimide precursor were simultaneously performed. After that, the positive photoresist is stripped with methylcellosolve acetate,
Furthermore, it was cured at 300 ° C. for 30 minutes. The thickness of the blue coloring layer was 2 μm. The first step of the spacer was formed on the resin black matrix simultaneously with the formation of the blue pixel. The size of the spacer was 20 μm square.

After the substrate was washed with water, the second step of the spacer was formed on the resin black matrix together with the formation of the green pixel in the same manner as the blue colored layer. The thickness of the green coloring layer is 2 μm,
The size of the spacer was 20 μm square.

Further, after the substrate was washed with water, the third step of the spacer was formed on the resin black matrix together with the formation of the red pixel in the same manner as in the formation of the blue coloring layer, thereby producing a color filter. The thickness of the red pixel portion was 2 μm, and the size of the spacer was 15 μm square.

A mixture of 7.5 g of the amic acid-based polyorganosiloxane solution obtained in Preparation Example 1, 10 g of the polyorganosiloxane solution obtained in Preparation Example 2, and 1.5 g of the chelate solution obtained in Preparation Example 3 were mixed with a transparent resin. A composition was obtained. The transparent resin is applied on the substrate on which the black matrix and the three primary color layers are formed, dried at 80 ° C. for 10 minutes, and then cured at 280 ° C. for 60 minutes to have a thickness of 0.5 μm.
Was formed.

On the substrate on which the transparent protective layer was formed, a film thickness of 140 nm and a surface resistance of 20 Ω /
The ITO film of □ was formed. The ITO film is formed on the entire surface except the outer edge of the color filter, and the size of the top is 10 μm.
Also formed on corner spacers.

The height of the spacer, which is the height from the surface of the ITO film to the top of the spacer, of the light transmitting portion provided on one colored layer, was 4.5 μm.

The area of the bottom of the spacer provided on the resin black matrix by lamination of the colored layers, that is, the area of the blue part was 400 μm ² , and the area of the top of the spacer in contact with the counter substrate was 100 μm ² . Also, spacers are provided on the frame formed of a resin black matrix around the screen by color superposition. Further, on the substrate outside the frame, the color filter and the spacer in the screen are formed by laminating the pattern of the resin layer used for the production of the resin black matrix and the pattern of the resin layer used for the production of the colored film similarly to the inside of the screen. A spacer was formed at the same time as the fabrication.

The substrate on which the transparent conductive film was formed was mounted on an XY stage of a YAG laser device (L-230 manufactured by HOYA), and a laser beam having an energy density of 10 J / cm ² was applied to the center of the spacer. Irradiation was performed on a range of 400 μm ² including the inclined portion. The laser light irradiation area of one pulse was 10 μm square, and the laser light was irradiated while moving the XY stage so as to cover the range of 400 μm ² including the overlap between the pulses. The transparent conductive film was similarly removed from the spacers on the entire screen.

The top of the spacer after laser irradiation was SEM
Measurement by XMA (scanning electron microscope-X-ray photoelectron analysis) confirmed that the ITO film had been removed. The spacer height was 4.36 μm, and the in-plane uniformity was good. Comparative Example 1 A color filter having a spacer was produced in the same manner as in Example 1. A polishing tape having a number of 10,000 was fixed on a polyethylene terephthalate film having a width of 10 mm and an alumina powder as an abrasive was fixed with a resin. The polishing tape was equipped with a winding function, and the spacer was polished while scanning over a color filter.

However, since the ITO film is harder than the colored layer, it has been difficult to find conditions for removing only the ITO film and not cutting the colored layer thereunder. Since the number of spacers under the polishing tape was reduced at the periphery of the screen, the polishing amount of the spacers was increased. When the height of the spacer at the center of the screen was 4.35 μm, the average of the heights of the spacers at the periphery of the screen was 4.1 μm, and the in-plane uniformity was not good. Example 2 In the same manner as in Example 1, a color filter having a spacer was produced. The periphery of the spacer was irradiated with a YAG laser at a width of 10 μm, avoiding a 10 μm square at the top of the spacer. Two laser beams branched from one laser oscillation device are shaped into a U shape through an optical system and a metal mask,
Together, a rectangular pattern having a width of 10 μm and surrounding the top was formed. The transparent conductive film was similarly removed from the spacers on the entire screen.

Since the laser beam is not irradiated on the spacer, the spacer height is the same as before the laser irradiation.
The uniformity was good at 5 μm.

[0079]

According to the method for manufacturing a color filter of the present invention, in order to keep the cell gap of the liquid crystal display device uniform,
Provided is a method for removing a transparent conductive film formed on a spacer with good in-plane uniformity when a spacer formed on a car filter is used without spraying a spherical spacer. By removing the transparent conductive film on the spacer, a short circuit between the color filter and the counter substrate can be avoided without restricting the design of the counter substrate.

[Brief description of the drawings]

FIG. 1 is an example of a cross-sectional view of a color filter substrate having fixed spacers of the present invention.

[Explanation of symbols]

 1: glass substrate 2: black matrix 3, 4, 5, 6, 7, 8: colored layer 9: transparent protective layer 10: transparent conductive layer 11: transparent conductive film removed portion

Claims (3)

[Claims] 1. A plurality of spacers each comprising at least two layers of a colored layer of three primary colors, a colored layer of the three primary colors, and a black matrix layer laminated on a substrate, and the colored layer and the spacers. A transparent conductive film formed so as to cover the spacer, wherein the transparent conductive film around the top of the spacer or the transparent conductive film around the top of the spacer and around the spacer is removed. 2. A method for forming a plurality of spacers by forming a colored layer composed of three primary colors on a substrate and laminating at least two layers of the colored layer composed of the three primary colors and a black matrix layer. A method for producing a color filter, comprising laminating a film, and then removing the transparent conductive film on the top of the spacer and / or around the top by light irradiation. 3. The method for producing a color filter according to claim 2, wherein said light irradiation is a laser light having a wavelength of 690 nm or more.