JPH08239575A - Polyamic acid composition, its production and color filter and its production - Google Patents

Abstract

PURPOSE: To obtain the subject composition without impairing polyimide resin characteristics, excellent in coatability on glass substrate, and useful for color filters, by reaction between a diamine and a tetracarboxylic dianhydride in a specific solvent. CONSTITUTION: In a solvent (A) consisting mainly of compound(s) of formula I and/or formula II ((n) is 1-3; R<1> is H or an alkyl; R<2> is H or an acyl; R<3> and R<4> are each H or an alkyl) (e.g. 2-butoxyethanol), (B) a diamine (e.g. a m- phenylenediamine) is reacted with (C) a tetracarboxylic dianhydride (e.g. pyromellitic dianhydride) e.g. at <=100 deg.C for 0.1-12h to obtain the objective composition. The compound in the component A is pref. of formula III (R is H or an alkyl).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polyamic acid obtained by reacting a diamine and a tetracarboxylic acid dianhydride, and particularly in the field of electronics such as semiconductors,
The present invention relates to a polyamic acid composition suitable for use in an interlayer insulating film, an insulating film, a light shielding film, a colored film, a protective film, an adhesive layer, etc., and a method for producing the same. The application will be described with reference to forming a coating film for a color filter for a liquid crystal display, but there is a wide range of applications other than that, and the composition is particularly thin and evenly coated with a polyimide varnish on a coating material. It can be advantageously used when desired.

[0002]

2. Description of the Related Art Generally, a polyimide resin is known as a polymer which is excellent in heat resistance and weather resistance and has good stability and electric characteristics. Due to its excellent properties, it is used in the electronic industry such as integrated circuits. The most general method is to obtain a polyimide cured product by subjecting a diamine and a tetracarboxylic acid dianhydride to a polyamic acid type precursor by a polyaddition reaction, and then subjecting the precursor to dehydration ring closure. Although some polyamic acid dissolves in diglyme and the like, good solvents for polyamic acid are N, N-dimethylacetamide (hereinafter referred to as DMAc) and N-methyl-2.
-The reaction solvent is limited to these because it is an amide-based solvent such as pyrrolidone (hereinafter referred to as NMP). Since these solvents have high boiling points, high flash points, high dissolving power, and low toxicity, they are excellent solvents that are easy to handle.Since these solvents are aprotic polar solvents, they are associated with hydrogen bond formation. However, it is suitable for industrial use because it increases the activity of diamine, which is a nucleophile, and accelerates the reaction.

However, when DMAc or NMP is used as a reaction solvent, it is difficult to obtain a polyamic acid solution having a high solid content and a low viscosity, and when it is used for forming a coating film such as a protective film for electronic parts, It was difficult to form a uniform coating film because of high viscosity, poor wettability, and difficulty in removing solvent. In order to improve these coatability, a method of polymerizing with a solvent of chloroform or tetrahydrofuran by using N-silylated diamine as a diamine, or dioxane and NMP as a polymerization solvent as disclosed in JP-B-56-163123. Method using dimethylformamide and lower alcohol, or JP-B-5
As disclosed in JP-A-6-163124, a proposal using dimethylformamide or NMP and a lower alcohol is disclosed.

[0004]

However, in these methods, there are problems that the heat resistance of the obtained polyimide film is not sufficient, and that ignition and explosion may occur due to mixing with a solvent having a low boiling point, and handling is not easy. It was

In order to improve the coating property, it is possible to dilute a general polyamic acid solution with a solvent having a relatively low boiling point or a solvent having a small surface tension. However, in a general polyamic acid solution, gelation and precipitation occur when diluted with these poor solvents, and shrinkage occurs during drying due to the low concentration, so that only a coating film having an uneven film thickness is obtained.

Therefore, the present inventors have proposed such heat resistance,
Provided is a polyimide precursor polyamic acid solution composition having improved coating properties on substrates, particularly glass substrates, without impairing the properties of the polyimide resin having excellent electrical properties and stability, and further providing a color filter having no coating defects. In order to achieve this, the present invention has been earnestly studied to provide the present invention.

[0007]

The object of the present invention is as follows.
Polyamic acid and the following general formulas (1) and / or (2) R ¹ -O- (CR ³ R ⁴ CH ₂ O) _n -R ² (1) R ¹ -O- (CR ³ R ⁴ CH ₂ CH ₂ O) _n —R ² (2) (In the formulas (1) and (2), n is an integer of 1 to 3, R ¹ is hydrogen or an alkyl group, R ² is hydrogen or an acyl group, R ³ ,
R ⁴ represents hydrogen or an alkyl group. ) A polyamic acid composition containing a compound represented by the formula (1) as an essential component, a method for producing a color filter comprising the step of applying this composition, and the above formula (1) and / or (2) In a solvent containing a compound represented as a main component, a method for producing a polyamic acid composition, which comprises reacting a diamine and a tetracarboxylic dianhydride, and a cured product of the polyamic acid composition. Is achieved by a color filter characterized by having

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION In the above formulas (1) and (2), R ¹ is hydrogen or an alkyl group, preferably C is an alkyl group having 1 to 10, and more preferably C is 1 to 6. Is an alkyl group. R ² is hydrogen or an acyl group, preferably hydrogen and an acyl group having C of 1 to 3, more preferably hydrogen or acetyl group, and further preferably hydrogen. R ³ and R ⁴ are hydrogen or an alkyl group, preferably hydrogen or an alkyl group having 1 to 3 carbon atoms, and more preferably hydrogen, a methyl group or an ethyl group.

Examples of such compounds include 1, 2
-Ethanediol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, 2- (isopentyloxy) ethanol, 2- (hexyloxy)
Ethanol, 1,3-propanediol, 2-methoxypropanol, 2-ethoxypropanol, 3-methoxypropanol, 3-ethoxypropanol, 2-methoxybutanol, 3-methoxybutanol, 3-methyl-3-methoxybutanol, diethylene glycol, There are diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol, triethylene glycol monomethyl ether, and acetates thereof. Among them, 2-butoxyethanol, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, 3- Methoxypropanol, 3-ethoxypropanol, 3-
Methyl-3-methoxybutanol, acetates thereof and the like can be mentioned. These compounds may be used alone or in combination of two or more. Further, amide solvents such as N, N-dimethylacetamide, N, N-dimethylformamide and N-methyl-2-pyrrolidone, ester solvents such as γ-butyrolactone and methyl 3-methoxypropionate, ethylene glycol diethyl ether. , And may be used as a mixture with an ether solvent such as diethylene glycol dimethyl ether. In that case, the solvent composition contains 50% by weight or more of the compound represented by the above formula (1) and / or (2). It is desirable that the content of these compounds be 80% by weight or more.

Further, a polyamic acid composition obtained by reacting a diamine and a tetracarboxylic dianhydride in a solvent composition containing a compound represented by the above formula (1) and / or (2) as a main component. It is more preferable to use a product. Here, the term “main component” means that the compound represented by the above formula (1) and / or (2) is contained in the solvent composition.
It means that it is contained in an amount of not less than 80% by weight, more preferably not less than 80% by weight.

Using these reaction solvents, a reaction temperature of 100
It is possible to obtain a polyamic acid having a relatively low degree of polymerization by terminating the polymerization at 0 ° C or less and within 0.1 to 12 hours, and as a result, at a high solid content concentration of 25% by weight or more, and Viscosity measured with a rotational viscometer is 1000 mP
It is possible to prepare a polyamic acid solution having a low viscosity of about a · s (25 ° C.). If the reaction temperature exceeds 100 ° C,
When the reaction time is 12 hours or more, imidization of the polyamic acid obtained according to this reaction system proceeds and the solubility in the solvent of the present invention decreases, resulting in gelation, polymer precipitation, viscosity increase, etc. May occur.

With the polyamic acid composition of the present invention, a polyamic acid solution composition having low viscosity, good wettability, less likely to cause gelation, and high solid content concentration is obtained, and a coating film having no coating defects is formed. can do.

Generally, a spinner, a roll coater, a wire bar coater, a die coater, etc. are used for uniform coating of these polyamic acid solution compositions. The coating defect in each coating method is caused by the solvent composition of the polyamic acid solution composition. Sometimes it can be solved by changing the. The polyamic acid solution composition of the present invention does not cause gelation and precipitation even when mixed with a poor solvent in the conventional polyamic acid solution composition and even when mixed with a poor solvent at a concentration at which a gel-like substance is precipitated. Due to these physical properties, the range of selection of the diluent solvent and the dilution ratio to be added for improving the coating defects is expanded.

The diamine used for the preparation of this polyamic acid is m-phenylenediamine, p-phenylenediamine, 4,4'-diaminodiphenylpropane,
4,4'-diaminodiphenylmethane, 2,7-diaminodiphenylfluorene, benzidine, 3,3'-dimethylbenzidine, 3,3'-dimethoxybenzidine,
4,4'-diaminodiphenyl sulfide, 3,3'-
(Or 4,4 ′-) diaminodiphenyl sulfone,
9,9'-bis (4-aminophenyl) sulfone, 4,
4'-diaminodiphenyl ether, 1,5-diaminonaphthalene, 2,4-bis- (β-amino-t-butyl) toluene, bis (p-β-methyl-o-aminobenzyl) benzene, 1,3-diamino -4-isopropylbenzene, 1,3-bis (3-aminophenoxy) benzene, 2,5-diaminotoluene, 2,5-diaminoparaxylene, 1,2-bis (3-aminopropoxy)
Ethane, 1,2-bis [4- (4-aminophenoxy)
Phenyl] propane, m-xylylenediamine, p-xylylenediamine, m-xylylenediamine, bis (4
-Aminocyclohexyl) methane, p, p'-tetramethyldiaminodiphenylmethane, p, p'-tetraethyldiaminodiphenylmethane, decamethylenediamine,
3-methylheptamethylenediamine, 4,4'-dimethylheptamethylenediamine, 2,1,1-dodecanediamine, 2,2-dimethylpropylenediamine, octamethylenediamine, 3-methoxyhexamethylenediamine, 2,5-dimethyl Hexamethylenediamine, 2,5
-Dimethylheptamethylenediamine, 3-methylheptamethylenediamine, 1,4-cyclohexanediamine,
3,3′-diaminodipropylamine, 1,6-diaminohexane, hexamethylenediamine, etc. are used,
These diamines can be used in combination. From the heat resistance of the polyimide, those having a structure in which the amide group of the polymer main chain is directly bonded from the aromatic ring, for example, m-phenylenediamine, p-phenylenediamine, 4,4′-diaminodiphenyl propane,
4,4'-diaminodiphenylmethane, 2,7-diaminodiphenylfluorene, benzidine, 3,3'-dimethylbenzidine, 3,3'-dimethoxybenzidine,
4,4'-diaminodiphenyl sulfide, 3,3'-
(Or 4,4 ′-) diaminodiphenyl sulfone,
9,9'-bis (4-aminophenyl) sulfone, 4,
4'-diaminodiphenyl ether, 1,5-diaminonaphthalene, 2,4-bis- (β-amino-t-butyl) toluene, bis (p-β-methyl-o-aminobenzyl) benzene, 1,3-diamino -4-Isopropylbenzene, 1,3-bis (3-aminophenoxy) benzene, 2,5-diaminotoluene, 2,5-diaminoparaxylene and the like are preferably used. Examples of the tetracarboxylic acid dianhydride include aliphatic and aromatic tetracarboxylic acid dianhydrides, and examples thereof include pyromellitic acid dianhydride and 3,3 ′, 4,4′-benzophenone tetracarboxylic acid dianhydride. , 2,2 ', 3,3'-benzophenone tetracarboxylic dianhydride, 3,3', 4,4'-biphenyltetracarboxylic dianhydride, 3,3 ', 4,4'-
Diphenyl sulfone tetracarboxylic dianhydride, 4,
4'-oxydiphthalic acid dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 1,2,3,4
-Cyclobutanetetracarboxylic dianhydride, 1,2,
3,4-cyclopentanetetracarboxylic dianhydride and the like can be mentioned. These tetracarboxylic dianhydrides can also be used in combination. From the heat resistance of the obtained polyimide, those having a structure in which the bond with the carbonyl group of the polymer main chain is directly formed from an aromatic ring or an aromatic heterocycle are preferable. For example, 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'-
Diphenyl sulfone tetracarboxylic dianhydride, 4,
4'-oxydiphthalic acid dianhydride and the like can be mentioned. Preferred combinations of these diamines and tetracarboxylic dianhydrides and compounds of the general formulas (1) and / or (2) include pyromellitic dianhydride and 3,3′-
(Or 4,4 ′-) diaminodiphenyl sulfone and diethylene glycol monoethyl ether, 3,3 ′,
4,4′-benzophenone tetracarboxylic dianhydride, 3,3 ′-(or 4,4 ′-) diaminodiphenyl sulfone and diethylene glycol monobutyl ether,
3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, 3,3'-(or 4,4 '-) diaminodiphenyl sulfone and diethylene glycol monomethyl ether, pyromellitic dianhydride and 3,3 ', 4,
4'-benzophenone tetracarboxylic acid dianhydride and 3,
3 '-(or 4,4'-) diaminodiphenyl sulfone and triethylene glycol, 3,3 ', 4,4'-
Benzophenone tetracarboxylic anhydride and 3,3'-
(Or, 4,4 ′-) diaminodiphenyl sulfone and bis (3-aminopropyl) tetramethyldisiloxane and diethylene glycol monoethyl ether are mentioned as typical examples, but not limited thereto. Further, for the purpose of improving the adhesiveness of the polyimide obtained from these polyamic acids, it is possible to copolymerize an aliphatic diamine having a siloxane structure or add an aminosilane to the extent that the heat resistance is not lowered. The copolymerization amount of the aliphatic diamine having the siloxane structure is preferably 1 to 10 mol% of the diamine component from the viewpoint of heat resistance. Further, the amount of aminosilane added is preferably 0.5 to 10 wt% with respect to the polyimide from the viewpoint of heat resistance. Further, a part of the tetracarboxylic acid dianhydride can be replaced with a dicarboxylic acid monoanhydride for the purpose of controlling the degree of polymerization.

Typical applications of the polyamic acid composition according to the present invention include protective films for color filters used in liquid crystal display devices and solid-state image pickup devices.
Further, by dispersing a coloring material such as a dye or a pigment or a light shielding material such as carbon black in the polyamic acid composition of the present invention, it can be used as a colored film or a light shielding film of a color filter. This is because these coating films such as a protective film, a colored film, and a light-shielding film are important for flattening and protecting the surface of the color filter and are required to have excellent coatability on the substrate.

[0016]

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.

Example 1 (Preparation of Polyamic Acid Solution Composition) Diethylene glycol monoethyl ether 162 was placed in a three-necked 3 l flask.
Add 1.15 g and stir under N ₂ aeration for 3,3 ′
-Diaminodiphenyl sulfone 232.33 g, bisaminopropyl tetramethyldisiloxane 7.194
g is added. After stirring for 30 minutes, 3,3 ', 4,4'-
Benzophenone tetracarboxylic acid anhydride 310.32
g was added together with 30 g of diethylene glycol monoethyl ether, 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. The mixture was allowed to stand overnight at room temperature to obtain a polyamic acid solution as a polyimide precursor. Polyamic acid concentration obtained with this formulation is 25 wt
%, And the rotational viscosity was 1011 mPa · s (25 ° C.).

Example 2 (Preparation of Polyamic Acid Solution Composition) Diethylene glycol monomethyl ether was added to an equal amount of diethylene glycol monoethyl ether, and 3,3'-diaminodiphenyl sulfone was added to an equivalent molar equivalent of diaminodiphenylmethane. Benzophenonetetracarboxylic acid dianhydride. A polyamic acid solution was obtained in the same manner as in Example 1 except that the substance was used instead of the equimolar equivalent of biphenyltetracarboxylic dianhydride. The solid content concentration of the polyamic acid solution obtained by this formulation is 25
%, And the rotational viscosity was 987 mPa · s (25 ° C.).

Example 3 (Preparation of Polyamic Acid Solution Composition) NMP (670 g) and 2-butoxyethanol (700) were placed in a three-necked 2 l flask.
Put g, N ₂ under aeration, stirring 3,3'-diaminodiphenyl sulfone 105.4 g, diaminodiphenylmethane 83.87G, adding bisaminopropyl tetramethyldisiloxane 13.42 g. After stirring for 30 minutes, biphenyltetracarboxylic dianhydride 26
When 0.43 g was added together with 30 g of NMP and completely dissolved, the temperature was raised to 60 ° C. The mixture was stirred for 2 hours while controlling the temperature at 60 ° C. A polyamic acid solution as a polyimide precursor was obtained. The polyamic acid solution obtained with this formulation had a solid content concentration of 25% and a rotational viscosity of 3010 mPa · s.
It was s (25 degreeC).

Comparative Example 1 NMP 1621.15 g was placed in a three-necked 3 l flask, and 32.3'-diaminodiphenylsulfone 232.33 g and bisaminopropyltetramethyldisiloxane 7.194 g were added under N ₂ aeration with stirring. .
After stirring for 30 minutes, 310.32 g of 3,3 ′, 4,4′-benzophenone tetracarboxylic acid anhydride was added to 30 g of N 2.
When gradually dissolved with MP and completely dissolved, 50
Raise the temperature to ℃. The mixture was stirred for 3 hours while controlling the temperature at 50 ° C.
The mixture was allowed to stand overnight at room temperature to obtain a polyamic acid solution as a polyimide precursor. The polyamic acid solution obtained with this formulation had a solid content concentration of 25% and a rotational viscosity of 11211.
It was mPa · s (25 ° C.).

Example 4 (Evaluation) The polyamic acid solution compositions prepared in Examples 1 to 3 were diluted with 2-butoxyethanol to a solid content concentration shown in Table 1 to prepare a coating solution. A spinner was applied to the substrate to obtain a sample for applicability evaluation. Table 1 shows the results of evaluation of coating properties of this sample. Table 1 shows the results of measuring the voltage holding ratio of the polyamic acid solution composition. Further, the results of measuring the storage stability and heat resistance of the polyamic acid solution composition are shown in Table 2.

The measurement method was as follows.

Coating property (irradiation unevenness): The coating property irradiation unevenness of the sample for evaluation was visually evaluated directly under a fluorescent lamp and a Na lamp.

Coating property (uniformity of film thickness): The film thickness was measured on a diagonal line including the rotation center of the evaluation sample in steps of 10 mm using a step thickness film thickness meter Surfcom 1500A manufactured by Tokyo Seimitsu Co., Ltd. The film thickness at the midpoint of the rotation center and the substrate angle was defined as the standard film thickness, and the width of film thickness fluctuation was evaluated as a percentage of the standard film thickness.

Voltage holding ratio: A polyamic acid solution composition was applied on an electrode substrate and cured by heating to obtain a polyimide film, and this substrate was opposed to a new electrode substrate, and the space between the substrates was filled with a dielectric to prepare a capacitor. An AC voltage was applied to this capacitor and the holding rate of the voltage was measured. Applied voltage is 5V, holding time is 16.7ms.

Storage stability: The obtained polyamic acid solution was stored at -15 ° C for 90 days and the change in viscosity before and after the storage was measured. The data are shown by the retention rate of viscosity.

Heat resistance: The obtained polyamic acid solution was applied to a spinner and cured at 300 ° C. for 30 minutes, and the glass transition temperature of the cured film was measured. The glass transition temperature is an index of substantial heat resistance.

[0028]

[Table 1]

[0029]

[Table 2]

As is clear from Tables 1 and 2, in Examples 1 to 3 of the present invention, a coating film without radiation unevenness could be formed.
On the other hand, in the comparative example, it was difficult to obtain a coating film without radiation unevenness. In addition, in Examples 1 to 3 of the present invention, it was possible to form a coating film having a small film thickness variation over the entire coating film. On the other hand, in the comparative example, it was difficult to obtain a uniform coating film. Further, according to the present invention, the obtained polyamic acid having a relatively low molecular weight could be treated in the same manner as the conventional polyamic acid in terms of voltage holding ratio, storage stability and heat resistance of the cure film.

Example 5 A colored resin layer containing a heat resistant pigment was patterned by photolithography on a glass substrate provided with a patterned chrome light shielding layer. The polyamic acid solution composition prepared according to the formulation of Example 1 was applied onto the glass substrate provided with the colored layer, and cured at 280 ° C. to form a polyimide protective film layer of about 1.0 μm to obtain a color filter. An excellent color filter without coating defects was obtained.

Example 6 A color filter was prepared in the same manner as in Example 5 except that a polyimide layer obtained by dispersing a pigment in a polyamic acid solution composition prepared according to the formulation of Example 3 was used as the coloring layer. Obtained. An excellent color filter without coating defects was obtained.

Example 7 As Example 5 except that as the light-shielding layer, a polyimide layer obtained by dispersing carbon black in the polyamic acid solution composition prepared according to the formulation of Example 3 was used in place of the chromium light-shielding layer. A color filter was obtained in exactly the same manner. An excellent color filter without coating defects was obtained.

Comparative Example 2 A color filter was obtained in the same manner as in Example 5 except that a polyimide layer obtained from the polyamic acid solution composition prepared according to the formulation of Comparative Example 1 was used as the protective film. When the obtained color filter was visually evaluated directly under a fluorescent lamp and a Na lamp, radiation unevenness was observed and it was not practical for a color filter.

[0035]

EFFECTS OF THE INVENTION According to the present invention, polyamide, which is a polyimide precursor having excellent coating properties on a substrate, particularly a glass substrate, without impairing the properties of the polyimide resin having excellent heat resistance, stability, and electrical properties An acid solution composition can be obtained.

Claims (8)

[Claims] 1. A polyamic acid and the following general formulas (1) and / or (2) R ¹ —O— (CR ³ R ⁴ CH ₂ O) _n —R ² (1) R ¹ —O— (CR ³ R ⁴ CH ₂ CH ₂ O) _n —R ² (2) (In the formulas (1) and (2), n is an integer of 1 to 3, R ¹ is hydrogen or an alkyl group, R ² is hydrogen or An acyl group, R ³ ,
R ⁴ represents hydrogen or an alkyl group. ) The polyamic-acid composition containing the compound represented by these as an essential component. 2. Polyamic acid and the following general formula (3) R ¹ —O— (CH ₂ CH ₂ O) _n —H (3) (In the formula (3), n is an integer of 1 to 3, R Is a hydrogen atom or an alkyl group.) The polyamic acid composition according to claim 1, containing a compound represented by the formula) as an essential component. 3. A method for producing a color filter, comprising a step of applying the polyamic acid composition according to claim 1. 4. A color filter comprising a cured product of the polyamic acid composition according to claim 1 as a coating film. 5. The color filter according to claim 4, wherein the coating film is a polyimide film. 6. The color filter according to claim 4, wherein the coating film is at least one of a protective film, a colored film and a light shielding film. 7. The following general formula (1) and / or (2) R ¹ -O- (CR ³ R ⁴ CH ₂ O) _n -R ² (1) R ¹ -O- (CR ³ R ⁴ CH ₂ CH ₂ O) _n —R ² (2) (In the formulas (1) and (2), n is an integer of 1 to 3, R ¹ is hydrogen or an alkyl group, R ² is hydrogen or an acyl group, R ³ ,
R ⁴ represents hydrogen or an alkyl group. ) The method for producing a polyamic acid composition, which comprises reacting a diamine and a tetracarboxylic dianhydride in a solvent containing a compound represented by the formula (4) as a main component. 8. The following general formula (3) R ¹ —O— (CH ₂ CH ₂ O) _n —H (3) (In the formula (3), n is an integer of 1 to 3, R is hydrogen or The method for producing a polyamic acid composition according to claim 7, wherein the reaction of the diamine and the tetracarboxylic dianhydride is carried out in a solvent containing a compound represented by an alkyl group) as a main component.