JPH08220326A - Color filter - Google Patents

Abstract

PURPOSE: To obtain a color filter comprising a transparent substrate, light- shielding layer, colored layer, adhesive layer and transparent protective layer, and to improve adhesion property between the transparent protective layer and the light-shielding layer or the substrate while high transparency is maintained by specifying the pencil hardness of the adhesive layer to <HB hardness. CONSTITUTION: This color filter consists of a transparent substrate, light- shielding layer, colored layer, adhesive layer and transparent protective layer. The light-shielding layer consists of a resin containing dispersion of metal chromium, molybdenum, tantalum, aluminum, oxides of these, carbon or black pigment. The colored layer consists of a binder resin containing dispersion of various pigments. As for the adhesive layer, a material having <HB pencil hardness is used. The resin of the adhesive layer is preferably a polyimide resin having a polymer expressed by formula as the main structural unit. As for the transparent protective layer, a silicone-modified resin is preferably used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color filter used for a liquid crystal display, a solid-state image pickup device and the like.

[0002]

2. Description of the Related Art Conventionally, in a color filter in which a light shielding layer, a coloring layer, an adhesion layer and a transparent protective layer are formed on a transparent substrate, the transparent protective layer has transparency, flatness, hardness, heat resistance,
Properties such as adhesion are required. Examples of such a transparent protective layer include an acrylic resin disclosed in JP-A-3-251819, an epoxy resin disclosed in JP-A-2-228630, a polyimide resin disclosed in JP-A-61-24905, and a special resin. Silicone resins and the like disclosed in JP-A-63-241076 are known.

[0003]

The relationship between these transparent protective layers is that when the adhesion to the colored layer or glass is improved, the surface hardness becomes low, and conversely, when the surface hardness is increased, the adhesion becomes worse. However, it was difficult to satisfy both characteristics at the same time.

On the other hand, a metal thin film, especially a metal chrome thin film, may be used as a light-shielding layer for the purpose of improving the contrast of a color filter, and when such a color filter is modularized, the electrode terminal portion has a transparent substrate. It is formed on the upper transparent protective layer via an adhesive. However, the above-mentioned transparent protective layer has a weak adhesion to the metal thin film portion or the adhesive portion of the electrode terminal portion, and there is a problem in obtaining a highly reliable color filter.

[0005]

The inventors of the present invention have made earnest studies in order to obtain a highly reliable color filter having high transparency in such a color filter, and have come to provide the present invention. It is a thing.

That is, the present invention comprises a transparent protective layer and a light shielding layer,
Alternatively, it is an object of the present invention to improve the adhesion between the transparent protective layer and the glass substrate to obtain a color filter having extremely high transparency and excellent reliability.

An object of the present invention is a color filter having a light-shielding layer, a coloring layer, an adhesive layer and a transparent protective layer formed on a transparent substrate, wherein the adhesive layer has a pencil hardness of HB or less. It is achieved by a color filter.

The present invention will be specifically described below.

The transparent substrate referred to in the present invention may be a sheet made of glass or transparent plastic.

The light-shielding layer used in the present invention is, for example,
Examples thereof include metal chromium, chromium oxide, molybdenum, tantalum, aluminum and oxides thereof, and a resin in which carbon or a black pigment is dispersed. Among these, metal chromium and chromium oxide are preferable from the viewpoint of light-shielding property and film forming property. is there. A metal thin film, especially a metal chrome thin film, is often used as the light-shielding layer. A light-shielding layer containing a resin and a black pigment as main components is also often used.

The colored layer is generally formed by dispersing various pigments in a resin component as a binder, or by coloring a resin with a dye. The pigments used here include organic pigments and inorganic pigments, with organic pigments being particularly preferred. Examples of organic pigments include, for example, R-88,122,144,146,149,168,177,202,209,216 as a red pigment, Y-17,24,83,93,94,108,109,110,138,147 as a yellow pigment,
G-7,36 as green pigment, B-15: 2,15: 3,15: as blue pigment
4,15: 6, and V-19,23,32,37 as purple pigment. The pigment is usually contained in the transparent resin composition in a dispersed state.

In the present invention, the colored layer preferably contains a polyimide resin as a binder component. The polyimide resin used here is not particularly limited, but for example, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and 3,3 ′-(or 4,4 ′-) diaminodiphenyl sulfone and Consists of 1,3-bis (3-aminophenoxy) benzene, 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, metaphenylenediamine, 3,3'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether One or more diamine compounds selected from the group are preferably used.

As a method for forming such a colored layer, there are a photolithography method, a printing method, an electrodeposition method and the like, and the method is not particularly limited to these methods.

In the present invention, it is important to use an adhesive layer having a pencil hardness of HB or less. As such an adhesion layer, for example, a polyimide resin having a pencil hardness of HB or less is preferably used. As the polyimide resin, for example, the following general formula (1)

Embedded image (In the formula, R ¹ is a trivalent or tetravalent organic group having at least two carbon atoms, and R ² is at least 2
A divalent organic group having 1 or more carbon atoms is shown. ) The thing containing the polymer shown by these as a main structural unit is mentioned.

As a concrete example of such a polyimide,
Pyromellitic dianhydride and 3,3'- (or 4,4
′ −) Diaminodiphenyl sulfone, 3,3 ′, 4
4'-benzophenone tetracarboxylic dianhydride, 3,
3 ′-(or 4,4 ′-) diaminodiphenyl sulfone, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, and 3,3 ′-(or 4,4 ′-) diaminodiphenyl sulfone , Pyromellitic dianhydride and 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 3,3 ′-(or 4,4 ′-) diaminodiphenyl sulfone, 3,3 ′, 4,4′-benzophenone tetracarboxylic acid anhydride, 3,3 ′-(or 4,4 ′-) diaminodiphenyl sulfone and bis (3-aminopropyl) tetramethyldisiloxane,
3,3 ′, 4,4′-benzophenone tetracarboxylic anhydride, 3,3 ′-(or 4,4 ′-) diaminodiphenyl sulfone and 3,3′-diaminodiphenylmethane, bis (3-aminopropyl) ) It is preferable to use a polyamic acid synthesized from tetramethyldisiloxane or the like to form a polyimide by heating or the like. The polyimide may be composed of only one represented by the above general formula, or may be a copolymer with another structural unit. Typical types of structural units used for copolymerization include structural units of polyether amic acid and polyester amic acid, but are not limited thereto.

Further, for the purpose of improving the adhesiveness of the layered body composed of the polyimide represented by the above formula (1), it is possible to copolymerize an aliphatic diamine having a siloxane structure within a range that does not lower the heat resistance. . The copolymerization amount of the aliphatic diamine having a siloxane structure is preferably 1 to 5 mol% of the diamine component from the viewpoint of heat resistance.

The pencil hardness referred to in the present invention is a general parameter showing the surface strength of a coating film, and a pencil hardness tester (manufactured by Yoshimitsu Seiki Co., Ltd., type C-) using a Mitsubishi Uni (manufactured by Mitsubishi Pencil Co., Ltd.) pencil. 221) according to JIS5400. As an evaluation standard, a pencil is applied with a weight of 300 grams and the pencil is repeatedly moved 5 times to move the pencil. When scratches are found 1 or less out of 5 times on the surface of the coating film, the hardness of the pencil is defined as the surface hardness of the sample. When the pencil hardness exceeds HB (F or more), the adhesion layer becomes hard and the adhesion between the transparent protective layer and the light-shielding layer or the transparent protective layer and the glass substrate is not relaxed, so that the adhesion becomes poor. When modularized with such a color filter, poor adhesion of the electrode terminal portion or poor adhesion of the seal portion may occur, resulting in a problem of lowering the product yield. HB
The following adhesion layers do not have such a trouble, and can be well between the hard materials, and the stress applied to both layers can be well relaxed. Therefore, it is more preferable that the adhesion layer has a pencil hardness of B.
It is the following. The film thickness of these adhesion layers is 0.01 to 0.5.
μm is suitable.

As the coating method of the adhesive layer, any method such as a spinner method, a roll coater method, a printing method, a dip book can be used.

The transparent protective layer formed on the adhesive layer of the present invention is not particularly limited, but a silicone-modified resin is preferably used in order to form a transparent protective layer having high surface hardness. Such a silicone-modified resin may be either a resin containing Si atoms in the main chain, a resin containing a side chain, or a resin containing a main chain and a side chain in the resin.

Examples of such a silicone-modified resin include general formula (2) R ³ _p Si (OR ⁴ ) 4- _p (2) (wherein R ³ is an organic group, R ⁴ is an alkyl group or an acyl group). And p represents an integer of 1 to 3), a polymer (b) of a hydrolyzate (a) of a compound represented by the formula (1), an alkyd-modified silicone resin, an epoxy-modified silicone resin, an acrylic-modified silicone resin, an imide. Modified silicone resin,
Examples include, but are not limited to, modified silicone resins such as polyester-modified silicone resin, urethane-modified silicone resin, phenol-modified silicone resin, and melamine-modified silicone resin. Among them, the imide-modified silicone resin is preferable in terms of flatness, crack resistance, chemical resistance, and heat resistance required as a protective film.

The polymer (b) is obtained by hydrolysis of the alkoxysilane compound represented by the above formula (2). Examples of the alkoxysilane compound include methyltrimethoxysilane, methyltriethoxysilane,
Methyltripropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltripropoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltripropoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldipropoxysilane, vinyl Trimethoxysilane,
Vinyltriethoxysilane, vinyltripropoxysilane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, vinylmethyldipropoxysilane, 3-
Glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropyltripropoxysilane, 3-glycidoxypropylmethyldipropoxysilane, 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropyltripropoxysilane, 3-methacryloxypropylmethyldipropoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyl Triethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropylmethyldiethoxysilane, 3,4-epoxycyclohexyltrimethoxysilane, 3,4 Epoxycyclohexyl triethoxysilane, 3,4-epoxycyclohexylmethyl-diethoxy silane, etc. 3,4-epoxycyclohexylmethyl dimethoxy silane. These alkoxysilane compounds can also be used in combination.
Particularly preferably, methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltripropoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethyldiethoxysilane and these. The polymer of is used.

The imide-modified silicone resin is not particularly limited, but for example, a polymer obtained from a copolymer of the above hydrolyzate (a) or its partial condensate and the following imide precursor (c) is used. Can be mentioned. Examples of the imide precursor (c) include an amic acid obtained by reacting a tetracarboxylic acid dianhydride with an amine represented by the following general formula (3).

H ₂ N- (CH ₂ ) _m -SiR ¹ _n (OR ² ) _3-n (3) (In the formula, R ¹ is an alkyl group or an aryl group, and R ² is an alkyl group or an acyl group. , M is an integer of 1 or more, n
Represents an integer of 0 to 2. ) Examples of the tetracarboxylic acid dianhydride include aliphatic and aromatic tetracarboxylic acid dianhydrides, but are not limited to the following, and examples thereof include pyromellitic dianhydride, 3,3 ′,
4,4'-benzophenone tetracarboxylic dianhydride,
2,2 ', 3,3'-benzophenone tetracarboxylic dianhydride, 3,3', 4,4'-biphenyltetracarboxylic dianhydride, 3,3 ', 4,4'-diphenylsulfone tetracarboxylic Acid dianhydride, 4,4'-oxydiphthalic acid dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,2,2 3,4-cyclopentanetetracarboxylic dianhydride and the like can be mentioned. These tetracarboxylic dianhydrides can also be used in combination.

Examples of the amino compound represented by the above formula (3) include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltripropoxysilane and 3-aminopropylmethyldimethoxy. Silane, 3-aminopropylmethyldiethoxysilane, 3-aminopropylmethyldipropoxysilane, 3-aminopropylethyldimethoxysilane, 3-aminopropylethyldiethoxysilane, 3-
Aminopropylethyldipropoxysilane, 3-aminopropyldimethylmethoxysilane, 3-aminopropyldimethylethoxysilane, 3-aminopropyldimethylpropoxysilane and the like can be mentioned. These amino compounds can also be used in combination. Particularly preferably methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltripropoxysilane, dimethyldiethoxysilane, phenyltrimethoxysilane, and phenyltriethoxysilane, and These polymers are desirable.

Further, a surfactant such as a silicone type or a fluorine type can be added for the purpose of improving the coating property. Of these, silicone-based surfactants are preferably used. As a coating method of this transparent protective layer, a spinner method,
It can be performed by an arbitrary method such as a roll coater method, a printing method, or a dip method.

A color filter can be obtained by forming a transparent electrode on the transparent protective layer thus formed by a conventional method such as vapor deposition or sputtering. The transparent electrode used in the present invention is not particularly limited,
Conventionally used transparent substrates and transparent electrodes can be used.

[0027]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to the following examples.

Reference Example 1 (Production of Polyimide Precursor) N-methyl-2-pyrrolidone (614 g) was placed in a three-necked 2 liter flask, and 3,3'-diaminodiphenyl sulfone (49.65 g), while stirring under N ₂ aeration. 39.66 g of 4'-diaminodiphenylmethane was added. After stirring for 20 minutes, 3,3 ',
4,4'-benzophenone tetracarboxylic dianhydride 1
26.16 g was gradually added together with a little N-methyl-2-pyrrolidone, and when completely dissolved, the temperature was raised to 50 ° C. The mixture was stirred for 3 hours while controlling the temperature at 50 ° C. To prepare the terminals, 1.66 g of maleic anhydride was added and the mixture was stirred for another hour. After standing at room temperature for a whole day and night, it was diluted to a solid content concentration of 11% with a mixed solvent of NMP and ethylene glycol monobutyl ether to obtain a polyamic acid varnish as a polyimide precursor.

Reference Example 2 (Production of imide-modified silicone resin) N was added to a round bottom flask.
-Methyl-2-pyrrolidone (131 g) was added, and 60 g of benzophenonetetracarboxylic acid dianhydride was charged while stirring under N ₂ aeration. After lowering the internal temperature to 6 ° C with an ice bath,
71 g of 3-aminopropyldiethoxysilane was added dropwise. After completion of dropping, the mixture was stirred at room temperature for 3 hours to obtain a brown solution (d).

290 g of methyltrimethoxysilane was placed in another round-bottomed flask, stirred and ice-cooled to bring the internal temperature to 6 ° C. 115 g of 0.1% acetic acid aqueous solution was added dropwise at an internal temperature of 30 ° C. or lower. After completion of dropping, remove the ice bath and stir for 3 hours,
The stirring was stopped to obtain a solution (e).

A flask was charged with 50 g of ethylene glycol monobutyl ether and 0.28 g of a silicone type surfactant ("Disparlon"# 1610 (manufactured by Kusumoto Kasei)), and the mixture was stirred for 1 hour while aeration with N ₂ . Next, reference example 2
The solution (d) (15 g) prepared in Example 1 and the solution (e) (37.5 g) prepared in Reference Example 2 were added and stirred for 1 hour to obtain an imide-modified silicone resin.

Example 1 (Production of Color Filter) A colored polyimide layer containing a heat resistant pigment was patterned by photolithography on a glass substrate provided with a patterned chrome light shielding layer. On a glass substrate provided with a colored polyimide layer, the polyamic acid varnish prepared in Reference Example 1 was applied by a spinner,
A polyimide adhesion layer was provided with a thickness of about 0.1 μm. Further, a transparent protective layer having a thickness of about 1 μm was prepared from the imide-modified silicone resin prepared in Reference Example 2 on the polyimide adhesion layer to prepare a color filter. At this time, the semi-cure and main cure of the adhesion layer and the transparent protective layer were performed under the following conditions.

Semi-cure: 100 ° C., 30 minutes, hot air oven Main cure: 300 ° C., 60 minutes, hot air oven

Reference Example 3 (Production of Polyimide Precursor) A three-necked 2 l flask was charged with N--
Add 614 g of methyl-2-pyrrolidone, and under N ₂ aeration,
3,3'-diaminodiphenyl sulfone 4 with stirring
7.68 g, 4,4'-diaminodiphenylmethane 3
8.07 g and 3.98 g of bisaminopropyltetramethyldisiloxane were added. After stirring for 20 minutes, 3,3
′, 4,4′-Benzophenone tetracarboxylic acid anhydride 1
26.16 g was gradually added together with a little N-methyl-2-pyrrolidone, and when completely dissolved, the temperature was raised to 50 ° C. While adjusting the temperature to 50 ° C., 1.66 g of maleic anhydride was added for terminal preparation which was stirred for 3 hours, and further stirred for 1 hour. After allowing to stand overnight at room temperature, it was diluted to a solid content concentration of 11% with a mixed solvent of N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether to obtain a polyamic acid varnish as a polyimide precursor.

Example 2 A color filter was manufactured in exactly the same manner as in Example 1 except that the polyamic acid varnish prepared in Reference Example 3 was applied to form an adhesion layer.

Example 3 As the acid anhydride of the polyimide precursor component for the adhesion layer, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride in Example 1 was used in an equimolar equivalent amount of biphenyltetracarboxylic acid. A color filter was produced in exactly the same manner as in Example 1 except that the polyamic acid varnish prepared in place of the dianhydride was used.

Reference Example 4 (Production of Imido-modified Silicone) 131 g of N-methyl-2-pyrrolidone was placed in a round bottom flask, and benzophenonetetracarboxylic dianhydride 6 was stirred under N ₂ aeration with stirring.
0g was charged. After the internal temperature was lowered to 6 ° C with an ice bath, 71 g of 3-aminopropyldiethoxysilane was added dropwise. After completion of dropping, the mixture was stirred at room temperature for 3 hours to obtain a brown solution (d).

Further, 150 g of methyltrimethoxysilane was placed in another round-bottomed flask, stirred and ice-cooled to bring the internal temperature to 6 ° C. 115 g of 0.1% acetic acid aqueous solution was added dropwise at an internal temperature of 30 ° C. or lower, and after the addition was completed, the ice bath was removed and the mixture was stirred for 3 hours, and then stirring was stopped to obtain a solution (e).

50 g of ethylene glycol monobutyl ether and 0.28 g of a silicone type surfactant ("Disparlon"# 1610 (manufactured by Kusumoto Kasei)) were charged in a flask and stirred for 1 hour while aeration with N _{2 was} carried out. Next, 15 g of the solution (d) and 37.5 g of the solution (e) were added and stirred for 1 hour to obtain the imide-modified silicone resin.

Comparative Example 1 A color filter was prepared in the same manner as in Example 1 except that the polyimide adhesion layer in Example 1 was replaced with the imide-modified silicone resin prepared in Reference Example 4.

Reference Example 5 (Production of imide-modified silicone resin) N was added to a round bottom flask.
-Methyl-2-pyrrolidone (131 g) was added, and 60 g of benzophenonetetracarboxylic acid dianhydride was charged while stirring under N ₂ aeration. After lowering the internal temperature to 6 ° C with an ice bath,
71 g of 3-aminopropyldiethoxysilane was added dropwise. After completion of dropping, the mixture was stirred at room temperature for 3 hours to obtain a brown solution (d).

Further, 50 g of methyltrimethoxysilane was placed in another round bottom flask, stirred and ice-cooled to bring the internal temperature to 6 ° C. 115 g of 0.1% acetic acid aqueous solution was added dropwise at an internal temperature of 30 ° C. or lower, and after the addition was completed, the ice bath was removed and the mixture was stirred for 3 hours, and then stirring was stopped to obtain a solution (e).

A flask was charged with 50 g of ethylene glycol monobutyl ether and 0.28 g of a silicone-based surfactant ("Disparlon"# 1610 (manufactured by Kusumoto Kasei)), and the mixture was stirred for 1 hour while aeration with N ₂ . Next, 15 g of the solution (d) and 37.5 g of the solution (e) were added and stirred for 1 hour to obtain an imide-modified silicone resin.

Comparative Example 2 A color filter was produced in exactly the same manner as in Example 1 except that the polyimide adhesion layer in Example 1 was replaced with the imide-modified silicone resin prepared in Reference Example 5.

Example 4 In the color filters of Examples 1 to 3 and Comparative Examples 1 to 3, a colored polyimide layer was patterned on a glass substrate provided with a patterned chrome light shielding layer, and a polyimide was formed thereon. After providing the adhesion layer with a thickness of about 0.1 μm, the pencil hardness was measured on the glass substrate. Then, after forming a transparent protective layer, apply this color filter to 80 ° C × 95% RH
It was left for 100 hours in the atmosphere described in 1. above, and a cross-cut tape peeling test was conducted in accordance with JIS-K-5400. The results are shown in Table 1.

[0046]

[Table 1]

As shown in Table 1, in Examples 1 to 3, the polyimide adhesion layer had a pencil hardness of HB or less, and after the transparent protective layer was formed, a wet heat treatment was performed and a tape peeling test was conducted. Was good at 10 points. However, in Comparative Examples 1 to 3, the pencil hardness of the adhesive layer was F or more, and the results of the wet heat treatment tape peeling test after forming the transparent protective layer were all 3 points or less.

[0048]

According to the present invention, the adhesion between the substrate of the color filter and the imide-modified silicone resin used as the transparent protective film can be surely improved, so that the transparency is very high and the reliability is high. It is possible to obtain a color filter having excellent properties.

Claims (4)

[Claims] 1. A color filter comprising a transparent substrate on which a light-shielding layer, a coloring layer, an adhesion layer and a transparent protective layer are formed.
A color filter, wherein the pencil hardness of the adhesive layer is HB or less. 2. The color filter according to claim 1, wherein the adhesion layer is a polyimide resin. 3. The color filter according to claim 1, wherein the colored layer contains a polyimide resin as a binder component. 4. The color filter according to claim 1, wherein the transparent protective layer is a silicone-modified resin.