JPH07292106A - Highly viscous low particle polyimide prepolymer solution and method for producing the same - Google Patents

Abstract

PURPOSE:To produce a polyimide prepolymer solution having a high viscosity, low in the content of particles, and suitable as an electronic part material or an optical material. CONSTITUTION:The method for producing the highly viscous low particle polyimide prepolymer solution from a diamine component and a tetracarboxylic acid dianhydride component as essential components in the presence of a solvent comprises reducing the solvent-soluble component among the diamine component and the tetracarboxylic acid dianhydride component to an amount less 0.1mol.% or more than the amount of the other component, reacting the diamine component with the tetracarboxylic dianhydride component in the solvent, filtering the reaction solution with a filter, mixing the filtrate with a filtrate produced by filtering the solution of the reduced component, and subjecting the diamine component and the tetracarboxylic acid dianhydride component to a polymerization reaction in an approximately equimolar ratio; and the highly viscous low particle polyimide prepolymer solution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a high-viscosity low-particle polyimide precursor solution which has a small content of particles and is suitable as an optical material and an electronic component material, and a high-viscosity low-particle polyimide precursor solution.

[0002]

2. Description of the Related Art Polyimide resins are used for surface protection films, interlayer insulating films, buffer coat films, etc. of various electronic parts such as semiconductors. This polyimide resin can form a flat film on a substrate having large irregularities as compared with an inorganic insulating film, but if many particles are contained in the varnish,
This is a problem because the flatness is lost or pinholes are generated to cause dielectric breakdown. In addition, a polyimide resin containing fluorine is used as an optical material because it has characteristics such as high light transmittance and low refractive index. Even when it is used as an optical material, a large amount of particles contained in the varnish causes a large amount of light scattering, which causes a problem. The relationship between the number of particles contained in the polyimide precursor solution and the loss based on light scattering is large when the particle content is large. Although the scattering loss tends to decrease as the particle content is reduced, especially when the number of particles of 0.5 μm or more is 1000 particles / ml or less, the scattering loss is small and the influence of light scattering by the particles can be improved.

Reducing the content of particles in the varnish can be achieved by performing filtration many times with a filter having a small pore size. Japanese Unexamined Patent Publication (Kokai) No. 5-186592 discloses that a diamine component and a carboxylic dianhydride component are mixed and dissolved and then filtered, and then polymerization is allowed to proceed. It is also known to use a filter having a pore size of around 0.2 μm, which is the smallest pore size available at that time. However, since there is generally a logarithmically inverse relationship between the filtration flow rate of the liquid to be treated and its viscosity, it takes a long time to process a high-viscosity varnish of 30 poise or more, and the filtration process Therefore, the viscosity changes, which is a problem in manufacturing. Therefore, high-viscosity varnish usually has to be filtered using a filter of 0.3 μm or more, and since the content of particles of 0.5 μm or more is 1000 particles / ml or more, it is not applicable to electronic component materials and optical materials. It wasn't enough.

In order to solve such a problem, JP-A-5-186592 discloses that a polyimide is prepared by using a solvent, a diamine component and a carboxylic acid dianhydride which have been previously filtered by a filter having a pore size of 0.2 μm or less. A method of synthesizing a precursor or a polyimide and further performing a filtration treatment with a membrane filter having a pore size of 0.2 μm or less is disclosed. However, in this method, as described above, when the final filtration treatment is performed, it takes time in the case of a high viscosity varnish having a poise of 30 poise or more, so that the viscosity changes and it is not practical. Also,
Similarly, JP-A-5-186592 discloses that when the solution viscosity of a diamine component and a carboxylic acid dianhydride component is slowly increased, the polyimide precursor has a solution viscosity of 30 poise or less. A method of removing particles by a filtration treatment with a membrane filter of 0.2 μm or less is disclosed. However, in this method, when the synthesis is performed on a large scale, if filtration takes a long time, the viscosity may increase to 30 poises or more during filtration, and filtration may not be possible, which makes practical application difficult.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, has a high viscosity and a small particle content, and is a polyimide precursor solution excellent in application to optical materials and electronic component materials, and The manufacturing method is provided.

[0006]

DISCLOSURE OF THE INVENTION The present invention is directed to a polyimide precursor solution synthesized from a diamine component and a carboxylic dianhydride component as main components in the presence of a solvent. The solvent-soluble component is reduced by 0.1 mol% or more than the other component, and the diamine component and the carboxylic dianhydride component are dissolved in the solvent and reacted, and then reduced to a solution filtered with a filter. After the solvent in which the other component is dissolved is filtered with a filter, the diamine component and the carboxylic acid dianhydride component are polymerized to be approximately equimolar, and the polymerization reaction is performed. And a high-viscosity low-particle polyimide precursor solution.

Examples of the polyimide precursor solution used in the present invention include a polyamic acid solution, a polyimide solution, a polyimide / isoindoloquinazolinedione imide solution, a polyether imide solution, and a polyamide imide solution.

The polyimide-based precursor solution is N-methyl-
2-pyrrolidone, N, N-dimethylacetamide, γ-
It is obtained by the reaction of a diamine component and a carboxylic acid dianhydride component in a polar solvent such as butyrolactone, dimethyl sulfoxide, diglyme.

The present inventors have investigated the filtration method, and have reduced the solvent-soluble component of the diamine component and the carboxylic dianhydride component by 0.1 mol% or more compared to the other component to remove the solvent. In the solution obtained by dissolving the diamine component and the carboxylic acid dianhydride component in the filter after the reaction, the solvent in which the reduced component is dissolved is filtered in the filter and then added, and the diamine component and the carboxylic acid dianhydride component are added. It was found that a polyimide precursor solution having a high viscosity and a low particle size can be produced by carrying out a polymerization reaction in a substantially equimolar amount. That is, when the diamine component or the carboxylic acid dianhydride component is dissolved in a solvent by reducing it by 0.1 mol% or more, the polymerization reaction proceeds slowly and the solution viscosity also rises gently. The reaction temperature is usually 10 to 50 ° C. And 3
Since the increase in viscosity is saturated at 0 poise or less, the filtration process with a filter having a fine pore size is completed in a short time. To this solution, after filtering the solvent in which the component of the reduced amount was dissolved with a filter, the diamine component and the carboxylic acid dianhydride component were added until they became close to equimolar, and the polymerization reaction proceeded again. It is possible to obtain a solution having a high viscosity and a high molecular weight and a small particle content. Further, the ultimate viscosity can be adjusted by the amount of the components added later. The reaction temperature is usually 10 to 50 ° C., and the reaction time is usually 30 minutes to 120 hours.

When the diamine component or carboxylic acid dianhydride component is added to the solvent in a proportion of 0.1 mol% or more, any solvent which can dissolve and does not react may be used, but generally N-methyl-2 is used. -Pyrrolidone, N, N-dimethylacetamide, γ-butyrolactone, dimethyl sulfoxide, diglyme and the like are used. The components soluble in these solvents are added in a reduced amount. If the undissolved component is added in a reduced amount, this component cannot be added after filtering with a filter, which is not preferable. When both the diamine component and the carboxylic dianhydride component are soluble in the solvent, either one may be reduced.

The solvent-soluble component of the diamine component and the carboxylic acid dianhydride component is 0.1 mol% or more, preferably 0.2 to 60 mol% because of the solubility of the component, and the solvent is used by reducing it from the other component. Dissolve and react. If it is less than 0.1 mol%, the solution viscosity increases rapidly, and the viscosity becomes high during the filter treatment, which makes filtration difficult.

The filter used in both steps of the present invention is preferably a filter having a pore size of 0.5 μm or less. When a filter having a pore size of more than 0.5 μm is used, the number of particles of 0.5 μm or more is 1000. Individual/
It is difficult to make it less than ml. More preferably, the pore size is 0.
A filter of 2 μm or less is used. The solution obtained by the above filtration method is sealed in a clean bottle as it is,
It is preferable to prevent the mixture of particles by performing a polymerization reaction in a clean bottle to increase the viscosity to a predetermined viscosity. According to the production method of the present invention, the viscosity of the solution is 30 poise or more, and the number of particles of 0.5 μm or more in the solution is 1000 particles /
It is possible to obtain a polyimide-based precursor solution having a volume of ml or less.

As the diamine component used for synthesizing the polyimide-based precursor solution, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane,
4,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfide, benzidine, metaphenylenediamine, paraphenylenediamine, 2,2-bis- (4-aminophenoxyphenyl) propane, 1,5
-Naphthalenediamine, 2,6-naphthalenediamine,
Bis- (4-aminophenoxyphenyl) sulfone, bis- (4-aminophenoxyphenyl) sulfide, bis- (4-aminophenoxyphenyl) biphenyl,
1,4-bis- (4-aminophenoxy) benzene,
1,3-bis- (4-aminophenoxy) benzene,
3,4'-diaminodiphenyl ether, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 4,4'-
Diaminodiphenyl ether-3-sulfonamide,
3,4'-diaminodiphenyl ether-4-sulfonamide, 3,4'-diaminodiphenyl ether-3 '
-Sulfonamide, 3,3'-diaminodiphenyl ether-4-sulfonamide, 4,4'-diaminodiphenylmethane-3-sulfonamide, 3,4'-diaminodiphenylmethane-4-sulfonamide, 3,4'-diaminodiphenylmethane -3'-sulfonamide 3,
3'-diaminodiphenylmethane-4-sulfonamide, 4,4'-diaminodiphenylsulfone-3-sulfonamide, 3,4'-diaminodiphenylsulfone-
4-sulfonamide, 3,4'-diaminodiphenylsulfone-3'-sulfonamide, 3,3'-diaminodiphenylsulfone-4-sulfonamide, 4,4'-diaminodiphenylsulfide-3-sulfonamide,
3,4'-diaminodiphenyl sulfide-4-sulfonamide, 3,3'-diaminodiphenyl sulfide-4-sulfonamide, 3,4'-diaminodiphenyl sulfide-3'-sulfonamide, 1,4-diaminobenzene- 2-sulfonamide, 4,4'-diaminodiphenyl ether-3-carbonamide, 3,4 '
-Diaminodiphenyl ether-4-carbonamide,
3,4'-diaminodiphenyl ether-3'-carbonamide, 3,3'-diaminodiphenyl ether-4
-Carboxamide, 4,4'-diaminodiphenylmethane-3-carbonamide, 3,4'-diaminodiphenylmethane-4-carbonamide, 3,4'-diaminodiphenylmethane-3'-carbonamide, 3,3'-diamino Diphenylmethane-4-carbonamide, 4,
4'-diaminodiphenylsulfone-3-carbonamide, 3,4'-diaminodiphenylsulfone-4-carbonamide, 3,4'-diaminodiphenylsulfone-
3'-carbonamide, 3,3'-diaminodiphenylsulfone-4-carbonamide, 4,4'-diaminodiphenylsulfide-3-carbonamide, 3,4 '
-Diaminodiphenyl sulfide-4-carbonamide, 3,3'-diaminodiphenyl sulfide-4-
Carbonamide, 3,4'-diaminodiphenyl sulfide-3'-sulfonamide, 1,4-diaminobenzene-2-carbonamide, 4- (1H, 1H, 11H
-Eicosafluoroundecanoxy) -1,3-diaminobenzene, 4- (1H, 1H-perfluoro-1-butanoxy) -1,3-diaminobenzene, 4- (1H,
1H-perfluoro-1-heptanoxy) -1,3-diaminobenzene, 4- (1H, 1H-perfluoro-1
-Octanoxy) -1,3-diaminobenzene, 4-pentafluorophenoxy-1,3-diaminobenzene,
4- (2,3,5,6-tetrafluorophenoxy)-
1,3-diaminobenzene, 4- (4-fluorophenoxy) -1,3-diaminobenzene, 4- (1H, 1
H, 2H, 2H-perfluoro-1-hexanoxy)-
1,3-diaminobenzene, 4- (1H, 1H, 2H,
2H-perfluoro-1-dodecanoxy) -1,3-diaminobenzene, (2,5-) diaminobenzotrifluoride, bis (trifluoromethyl) phenylenediamine, diaminotetra (trifluoromethyl) benzene, diamino (pentafluoro) Ethyl) benzene, 2,
5-diamino (perfluorohexyl) benzene, 2,
5-diamino (perfluorobutyl) benzene, 2,
2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl, 3,3'-bis (trifluoromethyl)
-4,4'-diaminobiphenyl, octafluorobenzidine, 4,4'-diaminodiphenyl ether, 2,
2-bis (p-aminophenyl) hexafluoropropane, 1,3-bis (anilino) hexafluoropropane, 1,4-bis (anilino) octafluorobutane,
1,5-bis (anilino) decafluoropentane, 1,
7-bis (anilino) tetradecafluoroheptane,
2,2'-bis (trifluoromethyl) -4,4'-diaminodiphenyl ether, 3,3'-bis (trifluoromethyl) -4,4'-diaminodiphenyl ether, 3,3 ', 5,5'- Tetrakis (trifluoromethyl) -4,4'-diaminodiphenyl ether, 3,
3'-bis (trifluoromethyl) -4,4'-diaminobenzophenone, 4,4'-diamino-p-terphenyl, 1,4-bis (p-aminophenyl) benzene,
p-bis (4-amino-2-trifluoromethylphenoxy) benzene, bis (aminophenoxy) bis (trifluoromethyl) benzene, bis (aminophenoxy)
Tetrakis (trifluoromethyl) benzene, 2,2-
Bis {4- (4-aminophenoxy) phenyl} hexafluoropropane, 2,2-bis {4- (3-aminophenoxy) phenyl} hexafluoropropane, 2,2
-Bis {4- (2-aminophenoxy) phenyl} hexafluoropropane, 2,2-bis {4- (4-aminophenoxy) -3,5-dimethylphenyl} hexafluoropropane, 2,2-bis {4 -(4-aminophenoxy) -3,5-ditrifluoromethylphenyl} hexafluoropropane, 4,4'-bis (4-amino-2)
-Trifluoromethylphenoxy) biphenyl, 4,
4'-bis (4-amino-3-trifluoromethylphenoxy) biphenyl, 4,4'-bis (4-amino-2)
-Trifluoromethylphenoxy) diphenyl sulfone, 4,4'-bis (3-amino-5-trifluoromethylphenoxy) diphenyl sulfone, 2,2-bis {4- (4-amino-3-trifluoromethylphenoxy) Phenyl} hexafluoropropane, bis {(trifluoromethyl) aminophenoxy} biphenyl, bis [{(trifluoromethyl) aminophenoxy} phenyl] hexafluoropropane, bis {2-[(aminophenoxy) phenyl] hexafluoroisopropyl} Examples include benzene.

All of the above diamine components are N-methyl-2-pyrrolidone, N, N-dimethylacetamide,
It is soluble in any of γ-butyrolactone, dimethyl sulfoxide, and diglyme.

As the carboxylic acid dianhydride component, p-terphenyl-3,4,3 ", 4" -tetracarboxylic dianhydride, pyromellitic dianhydride, 3,3 ', 4,4'
-Benzophenone tetracarboxylic dianhydride, 3,3 '
-4,4'-biphenyltetracarboxylic dianhydride,
3,3 ', 4,4'-biphenyl ether tetracarboxylic dianhydride, 1,2,5,6-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride 2,3,5,6-pyridinetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 4 , 4'-sulfonyldiphthalic acid dianhydride, 4,4'-oxydiphthalic acid dianhydride,
3,3 ′, 4,4′-tetraphenylsilane tetracarboxylic dianhydride, meta-terphenyl 3,4,3 ″,
4 ″ -tetracarboxylic dianhydride, 3,3′-4,4 ′
-Diphenyl ether tetracarboxylic dianhydride, 1,
3-bis (3,4-dicarboxyphenyl) -1,1,
3,3-tetramethyldisiloxane dianhydride, 1-
(2,3-Dicarboxyphenyl) -3- (3,4-dicarboxyphenyl) -1,1,3,3-tetramethyldisiloxane dianhydride (trifluoromethyl) pyromellitic dianhydride, di (Trifluoromethyl) pyromellitic dianhydride, di (heptafluoropropyl) pyromellitic dianhydride, pentafluoroethylpyromellitic dianhydride, bis {3,5-di (trifluoromethyl) phenoxy} pyro Mellitic dianhydride, 2,2'-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride, 5,5'-bis (trifluoromethyl)
-3,3 ', 4,4'-tetracarboxybiphenyl dianhydride, 2,2', 5,5'-tetrakis (trifluoromethyl) -3,3 ', 4,4'-tetracarboxybiphenyl dianhydride 5,5'-bis (trifluoromethyl) -3,3 ', 4,4'-tetracarboxydiphenyl ether dianhydride, 5,5'-bis (trifluoromethyl) -3,3', 4 4'-tetracarboxybenzophenone dianhydride, bis {(trifluoromethyl) dicarboxyphenoxy} benzene dianhydride, bis {(trifluoromethyl) dicarboxyphenoxy} (trifluoromethyl) benzene dianhydride, bis (di Carboxyphenyl) (trifluoromethyl) benzene dianhydride, bis (dicarboxyphenoxy) bis (trifluoromethyl) benzene dianhydride Anhydride, bis (dicarboxyphenoxy) tetrakis (trifluoromethyl) benzene dianhydride, 2,2-bis {(4- (3,4-dicarboxyphenoxy) phenyl} hexafluoropropane dianhydride,
Bis {(trifluoromethyl) dicarboxyphenoxy} biphenyl dianhydride, bis {(trifluoromethyl) dicarboxyphenoxy} bis (trifluoromethyl) biphenyl dianhydride, bis {(trifluoromethyl) dicarboxyphenoxy} diphenyl ether Examples thereof include dianhydride and bis (dicarboxyphenoxy) bis (trifluoromethyl) biphenyl dianhydride. When a polyamide-imide resin is obtained, trimellitic anhydride chloride or the like is used. As the carboxylic acid dianhydride component soluble in any of N-methyl-2-pyrrolidone, N, N-dimethylacetamide, γ-butyrolactone, dimethylsulfoxide and diglyme, 4,4′-
Examples thereof include oxydiphthalic acid dianhydride. Examples of the carboxylic dianhydride component insoluble in the solvent include pyromellitic dianhydride.

[0016]

EXAMPLES The present invention will be described below with reference to examples. Example 1 Using a 5 liter glass four-necked flask, 30 ml
2,2-bis (4
-Aminophenyl) hexafluoropropane 364.0
6 g (1.0900 mol) and N, N-dimethylacetamide 3736.41 g were charged and dissolved, and then 296.48 g (1.3600 mol) of pyromellitic dianhydride was added with stirring (diamine component / carboxylic acid). Dianhydride component = 0.8014 (molar ratio), diamine component is 2
0 mol% shortage). The monomer dissolved in 30 minutes and the viscosity at this time was 0.8 poise. This solution was put under a pressure of 1.5 kg / cm ² of dry nitrogen, a pore size of 0.2 μm and a diameter of 90 mm.
It was filtered with a Mitex membrane filter (trade name, manufactured by Japan Millipo Limited). Filtration was completed in 30 minutes and the viscosity at this time was 0.8 poise. 90.18 g (0.2700 mol) of 2,2-bis (4-aminophenyl) hexafluoropropane was added to this solution.
-Dissolved in 513.59 g of dimethylacetamide and added with the solution filtered through the Mitex membrane filter described above, mixed with stirring, dispensed into a 1 liter clean bottle, sealed and left at room temperature. The solution viscosity after standing for 24 hours was 500 poise. In addition, the number of particles in this solution was measured by a particle counter (KL-0 manufactured by Rion Co., Ltd.).
According to the measurement in 1), the number of particles of 0.5 μm or larger was 450 particles / ml.

Example 2 Using a 5 liter glass four-necked flask, 30 ml
4,4'-diaminodiphenyl ether 294.00 g (1.4700 mol) and N-methyl-2-pyrrolidone 3200 g were charged and dissolved while passing dry nitrogen at a flow rate of / min, and then dissolved in 4,4'-oxydiphthalic acid. 365.80 g (1.1800 mol) of dianhydride was added with stirring (diamine component / carboxylic acid dianhydride component =
1.2458 (molar ratio), the carboxylic dianhydride component is 2
0 mol% shortage). The monomer dissolved in 20 minutes and the viscosity at this time was 0.6 poise. This solution was put under a pressure of 1.5 kg / cm ² of dry nitrogen and had a pore size of 0.2 μm and a diameter of 90 mm.
It was filtered with a Mitex membrane filter of. Filtration was completed in 20 minutes, and the viscosity at this time was 0.6 poise. 89.90 g (0.2900 mol) of 4,4'-oxydiphthalic dianhydride was added to this solution.
-A solution prepared by dissolving in 1050 g of pyrrolidone and filtered through the above Mitex membrane filter was added, mixed with stirring, dispensed into a clean bottle of 1 liter, sealed and left at room temperature. The solution viscosity after standing for 24 hours was 400 poise. The number of particles of 0.5 μm or larger in this solution was 400 particles / ml.

Comparative Example 1 In Example 1, 454.00 g (1.35) of 2,2-bis (4-aminophenyl) hexafluoropropane
93 mol), N, N-dimethylacetamide 4250 g
Was charged and dissolved, and then pyromellitic dianhydride 29
6.48 g (1.3600 mol) was added with stirring (diamine component / carboxylic acid dianhydride component = 0.99
95 (molar ratio), 0.05 mol% of diamine component is insufficient). The monomer was dissolved in 30 minutes, but the viscosity at this time was already 60 poise and filtration by the Mitex membrane filter used in Example 1 was impossible, and a polyimide precursor solution with high viscosity and low particles could not be obtained. It was

Comparative Example 2 In Example 1, 454.24 g (1.36) of 2,2-bis (4-aminophenyl) hexafluoropropane
00 mol), N, N-dimethylacetamide 4250 g
Was charged and dissolved, and then pyromellitic dianhydride 29
6.48 g (1.3600 mol) was added with stirring (diamine component / carboxylic acid dianhydride component = 1.00).
00). The monomer dissolves in 30 minutes and the viscosity at this time is 6
It was 0 poise. This solution was dried with 1.5 kg / cm ^{2 of} dry nitrogen.
It was filtered with a Mitex membrane filter (trade name, manufactured by Japan Millipore Limited) having a pore diameter of 1.0 μm and a diameter of 90 mm under pressure. The filtration is completed in 2 hours and the solution is 1
It was dispensed into a liter clean bottle, sealed and left at room temperature. The solution viscosity after standing for 24 hours was 500 poise. The number of particles of 0.5 μm or more in this solution was 5000 particles / ml, and a polyimide precursor solution having high viscosity and low particles could not be obtained.

[0020]

EFFECTS OF THE INVENTION According to the present invention, since it has a high viscosity and a small content of particles, it is possible to produce a polyimide precursor solution which is excellent in application to electronic component materials and optical materials.

Claims (3)

[Claims] 1. In a polyimide precursor solution synthesized by using a diamine component and a carboxylic dianhydride component as main components in the presence of a solvent, a component soluble in the solvent among the diamine component and the carboxylic dianhydride component. Of 0.1 mol% or more than the other component, the diamine component and the carboxylic dianhydride component are dissolved in the solvent and reacted, and the solution filtered by a filter is a solvent in which the reduced component is dissolved. Is filtered after being filtered with a filter, and then added to cause a diamine component and a carboxylic acid dianhydride component to be in a substantially equimolar amount to carry out a polymerization reaction. A method for producing a high-viscosity low-particle polyimide precursor solution. 2. The solvent according to claim 1, wherein N-methyl-2
A method for producing a high-viscosity low-particle polyimide precursor solution containing pyrrolidone, N, N-dimethylacetamide, γ-butyrolactone, dimethylsulfoxide or diglyme. 3. A high-viscosity low-particle polyimide precursor solution obtained by the production method according to claim 1.