JP2001305328A - Method for manufacturing color filter and color filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a color filter and the color filter, which solves the problem of increase of the manufacturing cost caused by increase of the number of photomasks to be used in the color filter with post spacers arranged by lamination. SOLUTION: In the method for manufacturing the color filter for a liquid crystal display element with the post spacers arranged thereon and in forming the post spacers by laminating two or more kinds of coloring layers with photolithography, the method is characterized by using a photomask for formation of the coloring layers in common with respective colors while shifting it by a pitch size of a pixel, by making the photomask for the formation of the coloring layers contain a pattern for the formation of the post spacers and a pixel pattern and by making the pixel pattern exist in a position corresponding to that of the pattern for the formation of the post spacers shifted by the pitch size of the pixel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a color filter used for a liquid crystal display device.

[0002]

2. Description of the Related Art In order to maintain the thickness (cell gap) of a liquid crystal layer, a color liquid crystal display element conventionally used is generally provided with an electrode substrate having a thin film transistor (TFT), a plurality of scanning electrodes, and the like. Plastic beads or glass fibers are provided as spacers between the filter and the substrate on the filter side. Here, since spacers such as plastic beads are scattered in the airflow, it is not determined at which position (in-plane position) between the electrode substrate and the color filter side substrate. Therefore, there is a problem that the display quality of the liquid crystal display element is deteriorated due to scattering and transmission of light by the spacers located on the pixels.

A liquid crystal display element in which spacers such as plastic beads are used by scattering them has the following other problems. That is, since the spacer is spherical or rod-shaped and comes in contact with a point or line during cell crimping,
There was a drawback that the alignment film and the transparent electrode were damaged, and display defects were likely to occur. Further, the liquid crystal is contaminated due to the damage of the alignment film and the transparent electrode, and the voltage holding ratio is reduced, so that the display is likely to be uneven.

Also, in order to uniformly disperse the spacers in a stable airflow, the tact time is long and productivity is not good, or it is necessary to control the particle size distribution of the spacers with high precision, and the spacers are expensive. For this reason, it was difficult to obtain a stable display quality liquid crystal display element by a simple method.

Therefore, as described in JP-A-8-114809 and JP-A-10-82909, a method has been proposed in which a column functioning as a spacer is formed of a resin or the like on a color filter.

As a method of forming the pillars, there are a laminating method in which the black matrix and the colored layer are formed simultaneously and sequentially, and a post-installation method in which the pillars are finally formed after the color filter is completed. The former is more preferred because there is no

The color filter can be prepared by a dyeing method for dyeing a photosensitive dyeable medium formed by a photolithography method, a method of processing by a photolithography method using a photosensitive pigment dispersion composition, a non-coloring method, or the like. Forming colored parts by printing method or inkjet method as a low-cost manufacturing method, in addition to a method of processing by a photolithography method using a photosensitive pigment dispersion composition and a photosensitive resist, an electrodeposition method using a patterned electrode, and a low-cost manufacturing method There are ways to do that. But,
In order to form a color filter while forming columns by a lamination method, a method of processing using a photolithography method is used.

[0008] In the photolithography method, exposure is performed using a photomask serving as a matrix of a color filter.
Photomasks are very expensive, and the number of photomasks required is related to cost. This tendency becomes particularly noticeable as the size of the photomask becomes larger. Also, photomasks are indispensable for production and production becomes impossible if they cannot be used due to scratches or the like. Even at times, it is common to replace them immediately so that production can continue. In this case, the number of photomasks to be held is doubled, and the problem of cost becomes more remarkable.

In order to form the columnar spacer at a specific location, the pattern differs for each color in the lamination method. In the case of a general color liquid crystal display element, R (red), G
(Green), B (blue), and BM formed between each color
In order to form (black matrix), the number of photomasks is required to be BM, R, G, and B. In addition, if a preliminary plate at the time of production is included, eight plates are required, and the problem of cost is large.

[0010]

SUMMARY OF THE INVENTION In view of the above situation, the present invention relates to a method of manufacturing a color filter with a pillar by a lamination method, which has the same function as a color filter manufactured by a conventional method, and is colored. An object of the present invention is to provide a color filter manufacturing method and a color filter capable of reducing the number of layers of a photomask for a layer.

[0011]

The object of the present invention is to provide a method of manufacturing a color filter for a liquid crystal display device provided with a columnar spacer, wherein the columnar spacer is formed by laminating two or more types of colored layers by photolithography. In doing so, the colored layer photomask is used in common for each color and shifted by the pixel pitch, and the colored layer photomask includes a column forming pattern and a pixel pattern, and is obtained by moving the column forming pattern by the pixel pitch. The present invention can be attained by a method for manufacturing a color filter, characterized in that a pixel pattern is present in the color filter.

In the method of manufacturing a color filter for a liquid crystal display device provided with a columnar spacer, when forming the columnar spacer by laminating two or more types of colored layers by using a photolithography method, a photomask for the colored layer is formed. It is assumed that a pattern for off-screen spacer formation having a length of twice or more the pixel pitch is formed at a position outside the screen on the colored layer photomask by shifting the pixel pitch for each color in common. It can be achieved by a characteristic color filter manufacturing method.

Further, the present invention can be achieved by a color filter having an off-screen spacer having a structure in which a plurality of patterns having a length of twice or more of the pixel pitch are overlapped at a position outside the screen.

[0014]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in detail below.

The color filter of the present invention has a plurality of pixel patterns formed of a colored layer arranged on a substrate.

FIG. 6 shows an example of an overall view of a general color filter. FIG. 6 is an example of an overall view of a color filter. The color filter includes an area 15 inside the screen and an area 14 outside the screen.
Consists of The term “outside the screen” refers to an area other than the inside 15 of the screen. In the screen 15, a pixel pattern made of a colored layer and a columnar spacer are formed on a substrate. Outside the screen 14
Is formed with an off-screen spacer.

The coloring layer forming the pixel pattern generally includes three primary colors. That is, when color display is performed by the additive method, three colors of R (red), G (green), and B (blue) are used.
When primary colors are selected and color display is performed by the subtractive color method,
Three primary colors of C (cyan), M (magenta) and Y (yellow) are selected. Generally, an element including these three primary colors can be used as a unit to provide a color display picture element. The shape of the pixel pattern is not limited, but is generally a stripe shape or an island shape (rectangular shape). The distance to the next color pixel is called the pixel pitch.

The color filter of the present invention may be provided with a black matrix (BM) as required. The black matrix referred to here generally indicates a light-shielding region arranged between pixels, and is provided to improve display contrast of a liquid crystal display element.

Between the black matrices in the display screen,
Usually, a black matrix opening of (20 to 200) μm × (20 to 300) μm is provided, and a plurality of colored layers are arranged so as to cover at least this opening.
If there is a black matrix, the pixel pitch is defined by the distance between adjacent black matrix openings.

The substrate used for the color filter of the present invention is not particularly limited, but inorganic glass such as quartz glass, borosilicate glass, aluminosilicate glass, soda lime glass whose surface is silica-coated, and plastics A transparent substrate such as a film or a sheet is preferably used.

The black matrix may be formed of a metal such as chromium or nickel or an oxide thereof.
It is preferable to form a resin black matrix composed of a resin and a light-shielding agent from the viewpoint of manufacturing cost and waste disposal cost. It is also preferable to use a resin black matrix from the viewpoint of securing the height of the columnar spacer. The resin used for the resin black matrix is not particularly limited, but is a photosensitive or non-photosensitive material such as an epoxy resin, an acrylic resin, a urethane resin, a polyester resin, a polyimide resin, a polyolefin resin, and gelatin. Is preferably used. The resin for the black matrix is preferably a resin having higher heat resistance than the resin used for the pixel and the protective film, and a polyimide resin is preferably a resin having resistance to the organic solvent used in the process after the formation of the black matrix. Resins are particularly preferably used.

The polyimide resin is not particularly limited, but a resin obtained by imidizing a polyimide precursor by heating or using an appropriate catalyst is preferably used. In addition, in addition to the imide bond, amide bond,
A bond other than an imide bond such as a sulfone bond, an ether bond, and a carbonyl bond may be included.

As the light shielding agent for the black matrix,
Metal oxide powders such as carbon black, titanium oxide, titanium oxynitride, and iron tetroxide, metal sulfide powders, metal powders, pigments, and mixtures thereof can be used. Among them, carbon black and titanium oxynitride are particularly preferable because of their excellent light-shielding properties. Since carbon black with a good dispersion and small particle size mainly exhibits a brownish color tone,
It is preferable to mix a pigment of a complementary color to carbon black to make it achromatic.

When the resin for the black matrix is polyimide, the black paste solvent is usually N-methyl-2-pyrrolidone, N, N-dimethylacetamide,
Amide polar solvents such as N, N-dimethylformamide and lactone polar solvents such as γ-butyrolactone are preferably used.

As a method of dispersing a light-shielding agent such as a pigment of a complementary color to carbon black or carbon black,
For example, there is a method in which a light-shielding agent, a dispersant, and the like are mixed in the polyimide precursor solution and then dispersed in a disperser such as a three-roll mill, a sand grinder, and 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.

As a method for producing the resin black matrix,
For example, there is a method of performing patterning after applying and drying a black paste on a substrate. As a method for applying the black paste, a dip method, a roll coater method, a spinner method, a die coating method, a method using a wire bar, and the like are suitably used. After that, heat drying (semi-curing) using an oven or a hot plate is performed. Do. The semi-curing conditions vary depending on the resin, solvent and paste applied amount, but it is usually preferable to heat at 60 to 200 ° C. for 1 to 60 minutes.

The black paste film thus obtained is patterned by a photolithography method as described below. When the resin is a non-photosensitive resin, after forming a photoresist film thereon, or when the resin is a photosensitive resin, it is exposed or after forming an oxygen barrier film. Perform development. At the time of exposure, a photomask serving as a matrix of a black matrix is used. If necessary, the photoresist or the oxygen blocking film is removed, and the film is dried by heating (this cure). The curing conditions are slightly different depending on the amount of coating when a polyimide resin is obtained from the precursor,
It is common to heat for 60 minutes. Through the above process, a black matrix is formed on the substrate.

The thickness of the resin black matrix used in the present invention is preferably 0.5 to 2.5 μm, more preferably 0.8 to 2.0 μm. The thickness of the resin black matrix is important for securing the cell gap of the liquid crystal display element, and if the thickness is smaller than 0.5 μm, it is not preferable because the light shielding property becomes insufficient. Also,
When the film thickness is more than 2.5 μm, the light-shielding property can be secured, but the flatness of the color filter is sacrificed, and a step is likely to occur. When a surface step is formed, even if a transparent conductive film or a liquid crystal alignment film is formed on the color filter, the step is hardly reduced, and the alignment treatment by rubbing the liquid crystal alignment film becomes non-uniform, and the cell gap varies. For example, the display quality of the liquid crystal display element is deteriorated. In order to reduce the surface step, it is effective to provide a transparent protective film on the colored layer, but it is not perfect. Further, it is disadvantageous in that the structure of the color filter becomes complicated and the manufacturing cost increases.

The light shielding property of the black matrix is O
It is represented by D value (common logarithm of reciprocal of transmittance). In order to improve the display quality of the liquid crystal display device, the OD value is preferably 2.0 or more, more preferably 2.5 or more.
More preferably, it is 3.0 or more. 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.

The reflectivity of the black matrix is represented by a luminosity-corrected reflectivity (Y value) in the visible region of 400 to 700 nm in order to reduce the influence of the reflected light and improve the display quality of the liquid crystal display device. % Or less, more preferably 1% or less.

For the coloring layer, a resin colored with a coloring agent is used.

As a coloring agent used in the coloring layer, an organic pigment, an inorganic pigment, a dye, and the like can be preferably used.
Further, various additives such as an ultraviolet absorber, a dispersant, and a leveling agent may be added. As the organic pigment, phthalocyanine-based, aziraki-based, condensed azo-based, quinacridone-based, anthraquinone-based, perylene-based, and perinone-based pigments are preferably used.

As the resin used for the colored layer, a photosensitive or non-photosensitive material such as an epoxy resin, an acrylic resin, a urethane resin, a polyester resin, a polyimide resin, a polyolefin resin, and gelatin is preferably used. It is preferable to disperse or dissolve the colorant in these resins for coloring. As the photosensitive resin, there are types such as a photodecomposable resin, a photocrosslinkable resin and a photopolymerizable resin, and particularly, a monomer, an oligomer or a polymer having an ethylenically unsaturated bond and an initiator which generates a radical by ultraviolet rays. A photosensitive composition, a photosensitive polyamic acid composition, and the like are preferably used. As the non-photosensitive resin, those which can be developed with the above-mentioned various polymers are preferably used. However, heat-resistant resins capable of withstanding such heat in the process of forming a transparent conductive film and the process of manufacturing a liquid crystal display element are preferably used. Is preferable, and a resin having resistance to an organic solvent used in a manufacturing process of a liquid crystal display element is preferable. Therefore, a polyimide resin is particularly preferably used.

As a method of forming a colored layer, for example,
There is a method of performing patterning after applying and drying a colored paste on a substrate. As a method of obtaining a colored paste by dispersing or dissolving the colorant, after mixing the resin and the colorant in a solvent, three-roll, sand grinder, there is a method of dispersing in a dispersing machine such as a ball mill, The method is not particularly limited.

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

The colored paste film thus obtained is patterned by photolithography as described below, as in the case of the black paste film.

When the resin is a non-photosensitive resin, after forming a photoresist film thereon, or when the resin is a photosensitive resin, it is used as it is or an oxygen barrier film such as polyvinyl alcohol. After the formation, exposure and development are performed. If necessary, the photoresist or the oxygen blocking film is removed, and the film is dried by heating (this cure). The curing conditions are different depending on the resin, but when a polyimide resin is obtained from the precursor, it is usually 200 to 300.
It is common to heat at 1C for 1 to 60 minutes.

By the above process, a patterned colored layer is formed on the substrate. The above steps are repeated for each color type. Normally, three colors are used, so the process is repeated three times.

In the lamination method of the present invention, a columnar spacer is formed by a colored layer simultaneously with the pixel pattern. In the photolithography method, exposure is performed using a photomask as shown in FIG. FIG. 5 is a schematic view of a color filter exposure step using a photomask 10, and 11 is a substrate.

FIGS. 3 and 4 show an example of a photomask used in the conventional laminating method and a color filter produced as a result. 3 and 4 show an example of a conventional color filter with a columnar spacer and a photomask for a colored layer used for the color filter. The processing order is BM → G → B → R.

FIG. 3 is a view in the screen, and FIG. 3A shows the pattern of the photomask.
(A) -4 is for BM (black matrix), G
Photomasks for (green), B (blue), and R (red) are shown, respectively. FIG. 3B is a plan view of a color filter display section processed using the same, and FIG. 3C is a cross-sectional view of the columnar spacer 5. In the figure, 1 indicates an opening of a BM (black matrix), 2 indicates a pixel pitch,
Indicates a pixel pattern, and 4 indicates a columnar spacer.

FIG. 4 is a view of an off-screen spacer. As in FIG. 3, FIG. 4 (a) shows the pattern of the photomask, and FIGS. 4 (a) -1 to 4 (a) -4 show the patterns for BM (black matrix), G (green), (Blue), R
(Red) photomasks are shown. FIG. 4B is a plan view of a color filter (out-of-screen spacer) processed using the same, and FIG. 4C is a cross-sectional view thereof. In the drawing, reference numeral 8 denotes an off-screen spacer forming pattern.

As shown in FIG. 3, the columnar spacers 5 are formed by laminating the column forming patterns 4 on the pixel patterns. A pixel other than the pixel pattern is not formed in a pixel of a color without the columnar spacer 5.

In this case, it is necessary to use different photomasks for the respective colored layers. Therefore, three plates are required for R, G, and B separately, and a total of four plates including a BM (black matrix) is provided. Also, photomasks are indispensable for production and production becomes impossible if they cannot be used due to scratches or the like. Even at times, it is common to replace them immediately so that production can continue. Therefore, in this conventional example, eight plates are required including the preliminary plate.

On the other hand, FIGS. 1 and 2 show an example of a photomask used in the present invention and a color filter produced as a result. FIGS. 1 and 2 show an example of a color filter with a pillar and a photomask of the present invention. The processing order is BM → G → B → R.

FIG. 1 is a diagram in the screen. FIG. 1 (a) -1
Indicates a photomask for BM. As shown in FIG. 1 (a) -2, the colored layer photomask (common to R, G and B) is composed of a pixel pattern 3 and a column forming pattern 4, and the column forming pattern 4 is shifted by a pixel pitch of 2. The pixel pattern 3 always exists at the position 7 which is located. This photomask is used in common for each color, and is not shifted when forming the G pixel, is shifted right by the pixel pitch 2 when processing the B pixel, and is shifted left by the pixel pitch 2 when forming the R pixel. G, B, and R colored layers are formed. The color filters processed in the order of BM → G → B → R in this manner are shown in FIGS. 1 (b), 1 (c) and 1 (d). FIG.
FIG. 1B is a plan view of a color filter display unit, and FIG.
FIG. 1C is a cross-sectional view of the columnar spacer 5, and FIG.
-1 is a cross-sectional view (R pixel portion) of the pseudo spacer 6;
FIG. 1D-2 is a sectional view of the pseudo spacer 6 (B pixel portion).

A column spacer 5 is formed in the G pixel portion. This is the same as FIG. 3 of the conventional example. FIG. 1 of the present invention differs from the conventional example of FIG. 3 in that a pseudo spacer 6 is formed in the R and B pixel portions simultaneously with the columnar spacer 5. The pseudo spacer 6 is, as shown in FIG.
At least a portion has a structure in which the pixel pattern 3 covers the pillar forming pattern 4.

In this case, when the pixel pattern is formed, the resin flows out from the column forming pattern, and the pixel pattern is formed thinner than a normal pixel pattern. Therefore, the height of the pseudo spacer is lower than that of the columnar spacer. Therefore, even if the pseudo spacer is formed, L
It does not contribute to the CD cell gap. Therefore, it has a function similar to that of a conventional color filter with columnar spacers without a pseudo spacer.

FIG. 2 is a view outside the screen. FIG. 2 (a) -1
Indicates a pattern 8 of the BM photomask. FIG.
As shown in (a) -2, a pattern (R, R) having a length 9 that is at least twice the pixel pitch 2 is provided on the photomask for the colored layer.
8 (common to G and B). A color filter (spacer outside the screen) processed in the order of BM → G → B → R using this photomask in the same manner as in FIG.
It is shown in (c). FIG. 2B is a plan view of the color filter (out-of-screen spacer 16), and FIG. 2C is a cross-sectional view of the color filter (out-of-screen spacer 16).

Since a pattern having a length 9 which is at least twice the pixel pitch 2 is formed on the colored layer photomask, it is possible to form a portion where all the colors of R, G, and B overlap. The off-screen spacer can be formed at a desired height.

Since the off-screen spacer 16 can be formed at the same height as that of the conventional example shown in FIG. 4, it has the same function as the conventional color filter. This off-screen spacer 16
However, although the resin flows out in the same manner as the pseudo spacer 6 in the screen, the size of the pseudo spacer 6 is limited due to the presence of the black matrix window. The height can be prevented from being reduced by increasing. The off-screen spacer 16 is required to avoid adhesion to the electrode substrate during the production of the liquid crystal display element or as a support material when cutting glass. It is not relevant and does not require strict height. Therefore, the forming method as shown in FIG. 2 has the same function as that of the conventional example shown in FIG.

1 and 2, the color layer photomask may be a single plate. There are a total of two editions including the BM, and four editions including the preliminary edition.

As the shape of the columnar spacer, the area of the upper colored layer is preferably equal to or smaller than the area of the lower colored layer in order to obtain the strength of the column. If the area of the lower colored layer is smaller, cracks may occur around the upper colored layer when a liquid crystal display element is manufactured.

The area and arrangement of the columnar spacers in the present invention
The location is a color filter when creating a liquid crystal display element.
Greatly affected by the structure of the substrate facing the substrate. That
Therefore, if there is no restriction on the opposing substrate side,
The area and location are not particularly limited, but the size of the picture element
, The area of the top of the columnar spacer is 10
μm^Two ~ 1000 μm^Two It is preferred that 10μ
m^Two If it is smaller than the above, formation or lamination of a precise pattern
Is difficult and 1000 μm^Two If greater than
Depending on the shape of the spacer, the black
It will be difficult to completely place it in the Trix equivalent part
Not preferred. Placement is not necessarily black matrix
It does not need to be on the center line of the opening
Rather, they often shift to the left or right. Off-screen space
The area at the top of the sir is 50 μm ^Two 〜１０10000 μm^Two 
Is preferred. Precise putter to hit the periphery on the substrate
This is because processing is more difficult than on the screen.

The height of the columnar spacer (the total thickness of the black matrix and the colored layer) is preferably 1 μm or more and 10 μm or less. If it is less than 1 μm, it becomes difficult to control the cell gap. On the other hand, when it is larger than 10 μm, it is not preferable because formation of columns becomes difficult.

In the present invention, if necessary, a conductive film necessary for driving the liquid crystal may be formed. The conductive film is manufactured through a method such as dipping, chemical vapor deposition, vacuum evaporation, sputtering, or ion plating. As the conductive film used in the present invention, those having a low resistance value, high transparency, and which do not impair color display characteristics are preferable. As a specific example of a typical transparent conductive film, indium tin oxide (ITO), zinc oxide, tin oxide, or an alloy thereof can be used. The thickness of such a transparent conductive film is preferably from 0.01 to 1 μm, and more preferably from 0.03 to 0.5 μm.

In the color filter, a transparent protective film may be provided on the colored layer if necessary. However, when a transparent electrode is formed on a color filter, the transparent protective film is preferably formed before the formation of the transparent electrode in order to reduce loss of driving voltage.

The color filter of the present invention may include a thin film transistor element and a thin film diode (TF) as necessary.
D) Elements, scanning lines, signal lines, and the like may be provided.

The liquid crystal used is not particularly limited, but more preferably, a nematic liquid crystal or a smectic liquid crystal is used for obtaining a good display. The smectic liquid crystal includes a ferroelectric liquid crystal, an antiferroelectric liquid crystal, a thresholdless antiferroelectric liquid crystal, and the like.

Similarly, there is no particular limitation on the display system. For example, display methods using a nematic liquid crystal include a twisted nematic type (TN), a super twisted nematic type (STN), a vertical alignment type (VA), an in-plane switching type (IPS), and the like. Is raised. A system in which the alignment of these liquid crystals is divided, for example, a display system in which the vertical alignment is divided, for example, a so-called multi-domain vertical alignment type (MVA) (alignment control technology in MVA liquid crystal display, P117 EKISHO Vol.
3 No. 2 1999).

The color filter of the present invention and a color liquid crystal display device using the same are used for display screens of personal computers, word processors, engineering workstations, navigation systems, liquid crystal televisions, videos, etc., and also for liquid crystal projection. It is preferably used. 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, deflection 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]

Hereinafter, the present invention will be described in more detail with reference to preferred embodiments, but the efficacy of the present invention is not limited by the embodiments used.

Example 1 (Preparation of resin black matrix) 3, 3 ', 4, 4'
-Biphenyltetracarboxylic dianhydride, 4,4'-diaminodiphenyl ether and bis (3-aminopropyl) tetramethyldisiloxane were converted to N-methyl-2-
The reaction was performed using pyrrolidone as a solvent to obtain a polyimide precursor (polyamic acid) solution. Titanium black mill base was homogenized at 7000 rpm using a homogenizer.
The mixture was dispersed and filtered, and the glass beads were filtered to obtain a black mill base, which was diluted with a polyimide precursor solution to obtain a black paste.

(Preparation of Colored Layer Forming Paste)
(Red), G (green) and B (blue) pigments
dex No.65300 Dianthraquinone pigment represented by Pigment Red 177, 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 a polyimide precursor solution to obtain three types of R, G, and B colored pastes.

(Preparation of Color Filter) The above-mentioned black paste was applied to a non-alkali glass substrate (“OA-10 material” manufactured by Nippon Electric Glass) using a curtain flow coater, and dried at 130 ° C. for 10 minutes on a hot plate. A resin coating was formed. A positive type photoresist (“SRC-100” manufactured by Shipley Co.) was applied by a reverse roll coater, and prebaked at 100 ° C. for 5 minutes on a hot plate.
Using an exposure machine “XG-5000” manufactured by Dainippon Screen Co., Ltd., irradiation with 100 mj / cm ² ultraviolet light through a photomask was performed, and then a 2.05% aqueous solution of tetramethylammonium hydroxide was used. Then, the development of the photoresist and the etching of the resin coating film were simultaneously performed to form a pattern, the resist was peeled off with methyl cellosolve acetate, and imidized by heating at 290 ° C. for 10 minutes on a hot plate to form a black matrix layer. .
When the film thickness of the black matrix layer was measured, 1.5
0 μm, and the OD value was 4.0.

Next, G is placed on a resin black matrix substrate.
The paste was applied by a curtain flow coater and dried on a hot plate at 130 ° C. for 10 minutes to form a G resin coating film.
Thereafter, as in the case of the black paste, a positive photoresist was applied by a reverse roll coater, and prebaked at 100 ° C. for 5 minutes on a hot plate. Then, using the same exposure machine as in the case of the black matrix, irradiation was performed by irradiating 100 mj / cm ² ultraviolet rays through a photomask, and then developing the photoresist using a 2.05% aqueous solution of tetramethylammonium hydroxide. And etching of the resin coating film were simultaneously performed to form a pattern, the resist was stripped with methyl cellosolve acetate, and imidized by heating at 280 ° C. for 10 minutes on a hot plate to form a G colored layer. When the thickness of the colored layer at the opening of the black matrix was measured, it was 2.1 μm.

After washing with water, the above-mentioned B paste was applied to a substrate having a G color layer formed on a resin black matrix, and the B color layer was formed by pattern processing in the same manner as for the G color layer.
When the thickness of the colored layer at the opening of the black matrix was measured, it was 2.2 μm.

Further, after washing with water, the above-mentioned R paste was applied on a substrate on which a G and B colored layer was formed on a resin black matrix layer, and pattern processing was performed in the same manner to form an R colored layer. When the thickness of the colored layer at the opening of the black matrix was measured, it was 2.1 μm.

The photomask used was of the type shown in FIGS. In other words, the photomask for the colored layer is a common version.

The black matrix has an opening of 214 μm.
It was a rectangle of m × 58 μm, and the pixel pitch was 90 μm. The pixel pattern of the colored layer is a stripe having a width of 85 μm,
The column forming pattern was such that the B colored layer had a size of 27 μm × 22 μm, and the uppermost R colored layer had a size of 15 μm × 10 μm. The position of the center of the column was shifted to the right by 17.5 μm from the center line of the black matrix opening.
The off-screen pattern has a length of 270 μm, which is three times the pixel pitch, in the direction in which the photomask is shifted, and is 270 μm ×
It was 90 μm.

The height of the columnar spacer in the G pixel portion from the glass substrate is 7.0 μm, and the height of the pseudo spacer is 6.8 μm in the B pixel portion, 6.6 μm in the R pixel portion, and the height of the off-screen spacer. Was 7.1 μm.

Next, a curable composition obtained by reacting a hydrolyzate of γ-aminopropylmethyldiethoxysilane with 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride is obtained. The solution is mixed with the R, G, B
Spin-coated on a substrate on which a colored layer of
Heat treatment was performed for 0 minutes to form an overcoat film having a thickness of 0.8 μm, thereby forming a color filter.

(Preparation and evaluation of panel) A non-alkali glass substrate (“OA-10” manufactured by Nippon Electric Glass) and a color filter were used as a sealant “XN-21S” containing 0.5% of a 4 μm diameter rod fiber. And assembled with an air press type press device. Press pressure is 0.6 kg / cm ² , and press temperature is 60 ° C to 150 ° C.
The temperature was raised to 1.5 ° C at a rate of 1.5 ° C / min. The completed empty panel was subjected to vacuum annealing at 110 ° C. for 1 hour, followed by liquid crystal injection. When the cell gap of the panel thus obtained was measured, a result having an average value of 3.8 μm and a standard deviation of 0.03 μm was obtained.

Comparative Example 1 In the above example, only the photomask used in forming the color filter was changed, and the other conditions were exactly the same.

The photomask used was of the type shown in FIGS. That is, the photomask for the colored layer is R, G, B
There are a total of three separate editions.

The black matrix was the same as in the example. The pixel pattern of the colored layer is a stripe having a width of 85 μm,
The column forming pattern was such that the B colored layer had a size of 27 μm × 22 μm, and the uppermost R colored layer had a size of 15 μm × 10 μm. The position of the center of the pillar was shifted from the center line of the black matrix opening by 17.5 μm. The off-screen pattern is as follows: the R layer is 90 μm × 90 μm, and the B layer is
0 μm × 110 μm, G layer is 130 μm × 130 μm,
The BM layer was 150 μm × 150 μm.

The height of the columnar spacer from the glass substrate was 7.0 μm, and the height of the off-screen spacer was 7.1 μm.

When the cell gap of the panel thus obtained was measured, a result having an average value of 3.8 μm and a standard deviation of 0.03 μm was obtained.

[0079]

According to the present invention, the number of photomasks to be used can be reduced in a method of manufacturing a color filter with columnar spacers while maintaining the same performance as a color filter manufactured by a conventional manufacturing method.

[Brief description of the drawings]

FIG. 1 illustrates an example of a photomask pattern in a screen and a color filter (display unit) using the same in the present invention.
FIG. 2 is a plan view and a sectional view of a columnar spacer and a pseudo spacer.

FIG. 2 is a plan view and a sectional view of an example of an off-screen photomask pattern and a color filter (out-of-screen spacer) using the same in the present invention.

FIG. 3 is a plan view of an example of a photomask pattern in a screen in a conventional method, a color filter (display unit) using the same, and a cross-sectional view of a columnar spacer.

FIG. 4 is a plan view and a sectional view of an example of an off-screen photomask pattern and a color filter (out-of-screen spacer) using the same in a conventional method.

FIG. 5 shows a substrate and a photomask (cross-sectional view) during exposure.

FIG. 6 is an example of an overall view of a color filter.

[Explanation of symbols]

 1: BM (black matrix) opening 2: pixel pitch 3: pixel pattern 4: column forming pattern 5: columnar spacer 6: pseudo spacer 7: position shifted from column forming pattern by pixel pitch 8: off-screen spacer formation Pattern 9: Length twice or more the pixel pitch 10: Photomask 11: Substrate 12: Display unit 13: Frame 14: Outside screen 15: Inside screen 16: Outside screen spacer

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[Procedure amendment]

[Submission date] April 4, 2001 (2001.4.4)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction contents]

As a method of forming the pillars, there are a laminating method in which the black matrix and the colored layer are formed simultaneously and sequentially, and a post-installation method in which the pillars are finally formed after the color filter is completed. The former is more preferred because there is no In addition, it can be retrofitted on pillars formed by the lamination method.
There is also a hybrid method in which additional pillars are formed by the shaking method
However, in a broad sense, it can be considered as one of the lamination methods.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0079

[Correction method] Change

[Correction contents]

[0079]

According to the present invention, in a method of manufacturing a color filter with columnar spacers by a lamination method, the number of photomasks used can be reduced while maintaining the same performance as a color filter by a conventional manufacturing method. Can be. Also, it is necessary to install it on a pillar
There is also a hybrid method that additionally forms pillars, but this method
It is clear that the present invention is also effective against the law.

Claims (3)

[Claims] In a method of manufacturing a color filter for a liquid crystal display element provided with a columnar spacer, when forming a columnar spacer by laminating two or more kinds of colored layers by using a photolithography method, a photomask for the colored layer is used. The color layer photomask includes a column forming pattern and a pixel pattern, and is shifted from the column forming pattern by the pixel pitch so that the pixel pattern exists at a position shifted by the pixel pitch. A method for producing a color filter, comprising: 2. A pattern for forming an off-screen spacer having a length of at least twice the pixel pitch is formed at a position outside the screen on the photomask for the colored layer. Method for manufacturing color filters. 3. A color filter comprising an off-screen spacer having a structure in which a plurality of patterns having a length twice or more of a pixel pitch are overlapped at a position outside the screen.