JP3308038B2 - How to create a color filter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a color filter used in a liquid crystal display or the like, and more particularly to a method for forming a pattern pixel having a light shielding property.

[0002]

2. Description of the Related Art A color filter used in a full-color liquid crystal display has a light-shielding pattern pixel between each of R, G, and B pixels for the purpose of preventing light leakage and improving contrast. The light-shielding pattern pixels are formed using a metal film such as chromium or a material in which a black pigment or the like is dispersed in a photosensitive resin. In the case of a metal film such as chromium, the metal film is vapor-deposited on the entire surface of the glass substrate by means such as vapor deposition, and then a resist is applied, patterned, and etched to pattern the metal film. In this method, the process is very complicated, the yield is low, and there are problems in cost. On the other hand, a method of forming a pattern pixel having a light-shielding property using a photosensitive black resin in which a photosensitive resin and carbon are combined is known. In this case, in order to obtain a certain light-shielding property, a film thickness of several μm is required. It is necessary, and usually, to create a color filter, pattern pixels having light-shielding properties and R,
Since the G and B pixels have a certain degree of overlap at the present time, the surface of the color filter has irregularities. In order to obtain good flatness, a flattening layer is further provided thereon and the surface is polished.
Therefore, Japanese Patent Application Laid-Open Nos. Hei 3-209203 and Hei 4-6960 are disclosed.
For No. 2, a method of applying a black photosensitive resin layer on the entire surface after forming R, G, and B, exposing from the back surface, and forming a pattern pixel having a light shielding property in a gap between RGB is being studied. However, with these methods, it is very difficult to apply a black photosensitive resin layer between the R, G, and B pixels with the same film thickness as the R, G, and B over the entire surface. When a liquid crystal panel was prepared using the color filters described above, there was a problem that the cell gap was not uniform and display unevenness occurred.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a color filter having pattern pixels having good flatness and light-shielding properties over the entire surface. A second object of the present invention is to provide a method for forming a pattern pixel having a high light-shielding property.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a multicolor pattern formed by pixels each having one of the three primary colors of light on a transparent substrate and a light-shielding property for shielding a portion where the pixels do not exist. In a method of manufacturing a color filter provided with pixels having a specific coumarin compound on a transparent substrate,
Forming a multicolor pattern by using a colored photosensitive layer containing an object , forming a light-shielding photosensitive resin layer by transfer over the entire surface of the transparent substrate over the multicolor pattern, and activating light rays through the transparent substrate. Irradiating the light-shielding photosensitive resin layer, a step of developing the light-shielding photosensitive resin layer to form a light-shielding pixel in a portion where the multicolor pattern does not exist, Achieved by the method of making the characteristic color filter.

Hereinafter, the present invention will be described in detail. As a method of forming a multicolor pattern composed of R, G, and B pixels on a transparent substrate, all known methods such as a dyeing method, a printing method, a pigment dispersion method, an electrodeposition method, and a transfer method can be used. . R for the photosensitive wavelength region of the light-shielding photosensitive resin layer,
When the light transmittance of the G and B pixels exceeds 2%, it is preferable to add a light absorbing agent to the R, G and B pixels in advance to reduce the transmittance to 2% or less. Used in the present invention
The light absorber used is a coumarin-based compound. This bear
Phosphorus compounds are particularly preferred from the viewpoints of both heat resistance and light absorption.
Furthermore, when a multicolor pattern is formed using a photopolymerizable composition, it is also preferable that these photopolymerizations are not hindered. The above-mentioned heat treatment at 200 ° C. or higher is performed to harden one layer of the pattern pixels as necessary at the time of forming the color filter.

[0006] Coumarin compounds include those represented by the general formula (I):
Compounds represented by (II) or (III) can be mentioned.

[0007]

Embedded image

Here, R ₁ and R ₂ may be the same or different and represent hydrogen, amino group, dialkylamino group, monoalkylamino group, N-substituted aminoalkyl group, halogen or alkoxy group. Alkyl and alkoxy have 1 to 4 carbon atoms
Are preferred. R ₃ represents an alkyl group having 1 to 7 carbon atoms, preferably 1 to 4 carbon atoms. R ₄ and R ₅ may be the same or different and represent hydrogen or an alkyl group having 1 to 7 carbon atoms, preferably 1 to 4 carbon atoms. R ₆ and R ₇ may be the same or different and represent hydrogen, an alkyl group having 1 to 7 carbon atoms, preferably 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms.

Specifically, 7- {4-chloro-6- (diethylamino) -s-triazin-2-yl} amino} -3-phenylcoumarin 7- {4-methoxy-6- (diethylamino) -S-
Triazin-2-yl {amino} -3-phenylcoumarin 7- {4-methoxy-6- (diethylaminopropylamino) -s-triazin-2-yl {amino} -3-
Phenylcoumarin N- (γ-dimethylaminopropyl) -N ′-{3-phenylcoumarinyl- (7)} urea 3-phenyl-7- (4′-methyl-5′-n-butoxy-benzotriazolyl -2) Coumarin and the like. Among them, 7- $ 4
-Chloro-6- (diethylamino) -s-triazine-
2-yl {amino} -3-phenylcoumarin is particularly preferred.

In the present invention, a transfer material, a transfer method, and a development method used in a step of forming a light-shielding photosensitive resin layer by transfer over the entire surface of the transparent substrate covering the color filter are described in Japanese Patent Application No. 2-400047. , Japanese Patent Application No. 3-929
2. Japanese Patent Application No. 3-120223, Japanese Patent Application No. 3-15322
7. Japanese Patent Application Nos. 4-12980 and 4-64870
The photosensitive transfer material, transfer method and developing method described in (1) can be used.

When light is exposed through a transparent substrate (referred to as back exposure), the light source is selected according to the photosensitivity of the light-shielding photosensitive resin layer, and may be an ultrahigh-pressure mercury lamp, a xenon lamp, a carbon arc lamp, an argon laser, or the like. Known light sources can be used.

At this time, if the light transmittance of the R, G, B pixels with respect to the photosensitive wavelength region of the light-shielding photosensitive resin layer exceeds 2%, a light-shielding pattern having an optical density (OD) of 1.5 or more is used. In the case of forming a pixel, a light-cured light-shielding film remains on the R, G, and B pixels, and it is difficult to use the pixel as a color filter. If the light transmittance of the R, G, B pixels exceeds 2%, a light absorber or the like is added in advance to the R, G, B pixels as described above, or an optical filter is used as another method. In this case, only a desired wavelength region may be selectively extracted, and in this case, it is preferable to use an optical filter having a transmittance of 400% or more in the photosensitive wavelength region of the light-shielding photosensitive resin layer of 2% or less. Further, both may be combined. By this method, R,
The light-shielding photosensitive resin layer transferred onto each of the G and B pixels does not substantially cure when exposed through the substrate,
It can be removed by a subsequent development process. Hereinafter, the present invention will be described in more detail based on examples,
The present invention is not limited to these.

[0013]

[0014]

[0015]

[0016]

[0017]

[0018]

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029]

Example 1 A coating solution having the following formulation H1 was applied on a polyethylene terephthalate film temporary support having a thickness of 100 μm.
After drying, a thermoplastic resin layer having a dry film thickness of 20 μm was provided. Thermoplastic resin layer formulation H1: methyl methacrylate / 2-ethylhexyl acrylate / benzyl methacrylate / methacrylic acid copolymer (copolymer composition ratio (molar ratio) = 55/30/10/5, weight average molecular weight = 50000) 15.0 Parts by weight polypropylene glycol diacrylate (average molecular weight = 822) 6.5 parts by weight tetraethylene glycol dimethacrylate 1.5 parts by weight p-toluenesulfonamide 0.5 parts by weight benzophenone 1.0 parts by weight methyl ethyl ketone 30.0 parts by weight

Next, the following formulation B1 was placed on the thermoplastic resin layer.
And dried to a dry film thickness of 1.6 μm.
An intermediate layer having a thickness of m was provided. Separation layer formulation B1: Polyvinyl alcohol (PVA205, manufactured by Kuraray Co., Ltd., saponification ratio = 80%) 130 parts by weight Polyvinylpyrrolidone (PVP, K-90, manufactured by GAF Corporation) 60 parts by weight Fluorinated surfactant (Asahi Glass Co., Ltd.) 10 parts by weight of distilled water 3350 parts by weight

On a temporary support having the thermoplastic resin layer and the intermediate layer, a coating solution having the following formula C1 is applied.
After drying, a light-shielding photosensitive resin layer having a dry film thickness of 2 μm was formed. Formulation C1: Benzyl methacrylate / methacrylic acid copolymer (molar ratio = 70/30, intrinsic viscosity = 0.12) 30.00 parts by weight Pentaerythritol tetraacrylate 7.40 parts by weight Michler's ketone 0.04 parts by weight 2 (ο- Chlorophenyl) -4,5-diphenyl imidazole dimer 0.40 parts by weight Carbon black 2.80 parts by weight Hydroquinone monomethyl ether 0.01 parts by weight Methyl cellosolve acetate 280.00 parts by weight Methyl ethyl ketone 140.00 parts by weight

Further, a cover sheet of polypropylene (12 μm thick) was pressed on the light-shielding photosensitive resin layer to prepare a light-shielding photosensitive transfer material. The photosensitive wavelength of the light-shielding photosensitive resin layer is from 350 nm to 420 nm, and the main photosensitive wavelength when an ultra-high pressure mercury lamp is used as a light source is 365 nm.
(I-line) and 405 nm (h-line), and the OD was 1.5 (measured using a Macbeth densitometer). Next, red (R), blue (B), and green (G) colored photosensitive layers having the compositions shown in Table 1 below were formed. However, 7 to all the colors - ((4-chloro-6- (Shi Bu ethylamino) - s - triazin-2-yl) amino) -3 was added phenyl coumarin as a solid content of 8%. Table 1: Formulation of photosensitive layer R layer G layer B layer K layer ─────────────────────────────────―― Pensyl methacrylate / methacrylic acid copolymer 60.0 60.0 60.0 60.0 Methacrylic acid copolymer (molar ratio = 73/27 viscosity = 0.12) Pentaerythritol 43.2 43.2 43.2 43.2 Tetraacrylate 2- (o-chlorophenyl 2.5 2.5 2.5 2.5 diphenylimidazole dimer Irgasin red BPT (red) 5.4 --- --- --- Sudan blue (blue) --- 5.2 --- --- Copper phthalocyanine ( Green) --- --- 5.6 --- Carbon black (black) --- --- --- 5.6 Methyl cellosolve acetate 560 560 560 560 Methyl ethyl ketone 280 280 280 280 Using this, a glass substrate (thickness 1. 1mm) on top of R,
G and B color filters were prepared. In this case, heat treatment was performed at 220 ° C. for 20 minutes for each color to completely cure each pixel. The transmittance of the obtained i-line and h-line of each color pixel is
Table 2 shows the results.

[0034]

The coating sheet of the light-shielding photosensitive transfer material is peeled off, and the light-shielding photosensitive resin layer surface is coated with a laminator (VP-II manufactured by Taisei Laminator Co., Ltd.) on the color filter surface having the R, G, and B pixels. Pressurizing (0.8kg / c
m ² ) and bonding by heating (130 ° C.), and then peeling off at the interface between the temporary support and the thermoplastic resin layer, and removing the temporary support. Next, back exposure was performed using an ultra-high pressure mercury lamp from the side opposite to the color filter surface. At this time, as shown in Table 4, the transmittance of the h-line of B exceeded 2%.
Toshiba glass filter (UVD3) between light source and sample
The exposure amount was set to 100 mj / cm ² through 6c). Thereafter, development was performed with a 1% aqueous solution of sodium carbonate to remove unnecessary portions, and a light-shielding film was formed in each of the R, G, and B pixel gaps. The finished color filter had no overlap between the light-shielding film and the RGB layers, and had good flatness.

Example 2 7-((4-Chloro-6- (diethylamino) -S-triazin-2-yl) amino) -3-phenylcoumarin of Example 1 was converted to 7-((4-methoxy-6- A color filter was produced in the same manner as in Example 1 except that diethylamino) -s-triazin-2-yl) amino) -3-phenylcoumarin was used. At this time, the transmittances of the obtained i-line and h-line of each color pixel are as shown in Table 3 .

[0037]

Hereinafter, the same evaluation as in Example 1 was performed, and similar good results were obtained.

[0039]

The method of the present invention (self-alignment)
In this method, a photosensitive resin layer having a light-shielding property is transferred onto a multicolor pattern, and back exposure can be performed in a state where the light-shielding resin layer on the pixel is not substantially cured, so that a color filter having excellent flatness can be easily formed. Can be created.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G02B 5/20-5/28

Claims (4)

(57) [Claims] 1. A three primary color of light on a transparent substrate.
In the method of manufacturing a color filter provided with a multicolor pattern formed by pixels having a light-shielding property to shield a portion where the pixel does not exist and a portion where the pixel does not exist,
In the general formula (I), the general formula (II) or the general formula (III)
A step of forming a multicolor pattern using a colored photosensitive layer containing a coumarin-based compound represented, a step of forming a light-shielding photosensitive resin layer by transfer over the entire surface of the transparent substrate over the multicolor pattern, Irradiating an actinic ray through a transparent substrate to cure the light-shielding photosensitive resin layer, and developing the light-shielding photosensitive resin layer to form a light-shielding pixel in a portion where the multicolor pattern does not exist And a method of producing a color filter. Embedded image In the formula, R ₁ and R ₂ may be the same or different;
Group, monoalkylamino group, dialkylamino group, N
Substituted aminoalkyl group, halogen atom, or alcohol
Represents a xy group. R ₃ represents an alkyl group having 1 to 7 carbon atoms. R ₄ , R ₅ : may be the same or different;
Represents an alkyl group having a prime number of 1 to 7. R ₆ , R ₇ : may be the same or different;
An alkyl group having 1 to 7 primes and an alkoxy group having 1 to 4 carbons
Represents 2. The photosensitive wavelength range of the light-shielding photosensitive resin layer.
The light transmittance of the multicolor pattern pixel is 2% or less.
The color filter according to claim 1, wherein
How to make. 3. A light-shielding photosensitive tree through the transparent substrate.
Light transmittance of multicolor pattern pixels in the photosensitive wavelength region of the oil layer
Irradiating light having a wavelength of not more than 2%
The method for producing a color filter according to claim 1, wherein 4. A light source between an actinic light source and a transparent substrate.
At least 400 nm of the photosensitive wavelength range of the light-shielding photosensitive resin layer
A filter having a light transmittance of 2% or less for the above wavelengths is provided.
The color filter according to claim 1, wherein
How to create