JP2016155979A - Polyimide precursor solution composition and method for producing polyimide film using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyimide precursor solution composition having a high concentration and a low solution viscosity, which can produce a polyimide film excellent in heat resistance, mechanical characteristics or the like.SOLUTION: There is provided a polyimide precursor solution composition which comprises an aromatic tetracarboxylic acid component and an aromatic diamine component comprising an aromatic tetracarboxylic acid diester, where 50 mol% or more of the aromatic tetracarboxylic acid component comprises a 3,3',4,4'-biphenyltetracarboxylic acid diester, the aromatic diamine component contains p-phenylene diamine and 4,4'-diaminodiphenyl ether, the ratio of the paraphenylenediamine in the aromatic diamine component is 50 mol% and the composition comprises imidazoles.SELECTED DRAWING: None

Description

  The present invention relates to a polyimide precursor solution composition and a method for producing a polyimide film using the same.

  In general, a polyimide film is coated with a polyamic acid solution obtained by polymerizing aromatic tetracarboxylic dianhydride and aromatic diamine, which are raw materials, in an organic solvent, and this is heated to remove the solvent. And imidized. However, since the polyamic acid has a large molecular weight, if the concentration of the polyamic acid in the solution is increased, the solution becomes highly viscous and difficult to handle.

  In order to solve this problem, a method using a polyimide precursor solution (nylon salt type monomer solution) composed of an aromatic tetracarboxylic acid diester and an aromatic diamine component has been proposed (Patent Documents 1 and 2).

Japanese Patent Laid-Open No. 10-182820 JP 2005-247987 A

  A polyimide precursor solution (nylon salt type monomer solution) in which an aromatic tetracarboxylic acid diester and an aromatic diamine are dissolved in a solvent can have a high concentration and a low solution viscosity, but the resulting polyimide becomes crystalline. In some cases, a combination of monomers cannot provide a polyimide film having sufficient characteristics. In particular, when a 3,3 ′, 4,4′-biphenyltetracarboxylic acid compound is used as a tetracarboxylic acid component and p-phenylenediamine is used as a diamine component, a crystalline polyimide resin is easily obtained, and a nylon salt monomer There was a problem that it was difficult to obtain a polyimide film having sufficient characteristics from the solution.

  An object of this invention is to provide the polyimide precursor solution composition of a high concentration and a low solution viscosity which can manufacture the polyimide film excellent in heat resistance, a mechanical characteristic, etc.

The present invention relates to the following items.
1. A polyimide precursor solution composition comprising an aromatic tetracarboxylic acid component comprising an aromatic tetracarboxylic acid diester and an aromatic diamine component,
The aromatic tetracarboxylic acid component is composed of 3,3 ′, 4,4′-biphenyltetracarboxylic acid diester in an amount of 50 mol% or more,
The aromatic diamine component contains p-phenylenediamine and 4,4′-diaminodiphenyl ether, and the proportion of paraphenylenediamine in the aromatic diamine component is 50 mol% or more,
A polyimide precursor solution composition comprising imidazoles.
2. The polyimide precursor solution composition according to item 1, wherein the solution viscosity is 0.01 Pa · s or less when the concentration of the polyimide precursor composed of the aromatic tetracarboxylic acid component and the aromatic diamine component is 20% by mass. object.
3. The manufacturing method of the polyimide film which apply | coats the polyimide precursor solution composition in any one of said claim | item 1 or 2 to a base material, and imidizes by heating.
4). Item 4. The method for producing a polyimide film according to Item 3, wherein the polyimide precursor solution composition is applied by an inkjet method.

  The polyimide precursor solution composition of the present invention has a high concentration and a low solution viscosity, and a polyimide film having sufficient characteristics can be obtained even though the resulting polyimide is a combination of monomers that are crystalline. Therefore, the polyimide precursor solution composition of the present invention can be suitably used as an inkjet ink.

  The present invention is a polyimide precursor solution composition in which an aromatic tetracarboxylic acid component composed of an ester of an aromatic tetracarboxylic acid, an aromatic diamine component, and imidazoles are dissolved in an organic solvent. Examples of the aromatic tetracarboxylic acid ester include aromatic tetracarboxylic acid diesters (also referred to as half esters). Specifically, two of the four carboxyl groups of the aromatic tetracarboxylic acid are carboxyl groups. Examples thereof include compounds in which a group is esterified and one of two adjacent carboxyl groups on an aromatic ring is esterified. Examples of the ester in the aromatic tetracarboxylic acid diester include lower alkyl esters, preferably alkyl esters having 1 to 3 carbon atoms such as dimethyl ester, diethyl ester and dipropyl ester.

  In the present invention, the aromatic tetracarboxylic acid component is mainly, ie, 50 mol% or more, preferably 70 mol% or more, particularly preferably 90 mol% or more of 3,3 ′, 4,4′-biphenyltetracarboxylic acid. It consists of an acid diester. Examples of the ester include alkyl esters having 1 to 3 carbon atoms such as dimethyl ester, diethyl ester, and dipropyl ester.

  The aromatic tetracarboxylic acid diester can be produced by a known method. For example, it is easy to react with the corresponding aromatic tetracarboxylic dianhydride in an amount of 2 times or more, preferably 2 to 3 times the amount of alcohol (lower alcohol, preferably an alcohol having 1 to 3 carbon atoms). Can be manufactured. In this method, the acid anhydride ring of the raw material reacts with alcohol to open a ring, resulting in a diester (half ester) having an ester group and a carboxyl group on adjacent carbons on the aromatic ring.

  In the present invention, an aromatic tetracarboxylic acid component (aromatic tetracarboxylic acid diester) other than 3,3 ′, 4,4′-biphenyltetracarboxylic acid diester may be used in an amount of 50 mol% or less. The tetracarboxylic acid diester that can be used in combination with 3,3 ′, 4,4′-biphenyltetracarboxylic acid diester is not particularly limited. For example, pyromellitic acid diester, 2,3,3 ′ , 4′-biphenyltetracarboxylic acid diester, 3,3 ′, 4,4′-benzophenone tetracarboxylic acid diester, oxydiphthalic acid diester, and the like can be preferably exemplified. The aromatic tetracarboxylic acid diester to be used need not be one kind, and may be a mixture of plural kinds.

  In the present invention, the aromatic diamine component is mainly composed of p-phenylenediamine and 4,4′-diaminodiphenyl ether, ie, 50 mol% or more, preferably 70 mol% or more, particularly preferably 90 mol% or more. . Moreover, it is preferable that the ratio of the paraphenylenediamine in an aromatic diamine component is 50 mol% or more, especially 50-85 mol%. If the proportion of paraphenylenediamine is too large, a polyimide film having good characteristics may not be obtained.

  In the present invention, an aromatic diamine component other than p-phenylenediamine and 4,4'-diaminodiphenyl ether may be used. The aromatic diamine that can be used is not particularly limited, and examples thereof include 4,4′-diaminodiphenylmethane, m-phenylenediamine, 2,4-diaminotoluene, 1,3-bis (4-aminophenoxy). ) Benzene, 1,4-bis (4-aminophenoxy) benzene, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, m-xylylenediamine, p-xylylenediamine, 2,2- Bis [4- (4-aminophenoxy) phenyl] propane, 4,4′-methylenebis (2,6-xylidine), α, α′-bis (4-aminophenyl) -1,4-diisopropylbenzene and the like are preferable. Can be listed. The aromatic diamine to be used need not be one kind, and may be a mixture of plural kinds.

化学式（１）において、Ｘ^１〜Ｘ^４は、それぞれ独立に、水素原子、又は炭素数が１〜５のアルキル基である。 The polyimide precursor solution composition of the present invention further contains imidazoles. Although it does not specifically limit as imidazole, The compound of following Chemical formula (1) can be mentioned suitably.

In the chemical formula (1), X ^{1 to} X ⁴ are each independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

In the imidazoles of the chemical formula (1), X ^{1 to} X ⁴ are each independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and at least two of X ^{1 to} X ⁴ are More preferred are imidazoles that are alkyl groups having 1 to 5 carbon atoms, that is, imidazoles having two or more alkyl groups as substituents. Examples of imidazoles having two or more alkyl groups as a substituent include 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 4-ethyl-2-methylimidazole, and 1-methyl-4-ethylimidazole. Etc. are suitable.

  Although the usage-amount of imidazoles is not specifically limited, 1-50 mass% is preferable with respect to the total amount of aromatic tetracarboxylic-acid diester and aromatic diamine, and 5-20 mass% is more preferable.

  The polyimide precursor solution composition of the present invention is prepared by using the above-mentioned aromatic tetracarboxylic acid diester and aromatic diamine in substantially equimolar amounts and uniformly dissolving in an organic polar solvent together with the above-mentioned imidazoles. Can do. When these components are dissolved, they may be heated as necessary. In the organic polar solvent, the carboxylate ion of the aromatic tetracarboxylic acid diester and the ammonium ion of the aromatic diamine form an ion pair, which is considered to be substantially a mixture of monomers. .

  Formation of the polyimide film using the polyimide precursor solution composition of the present invention is performed by applying the polyimide precursor solution composition onto the substrate and then imidizing it by raising the temperature continuously or stepwise. In general, it is said that the condensation reaction of an aromatic carboxyl group and an aromatic amino group does not proceed in the absence of a strong dehydration catalyst. Therefore, when using the polyimide precursor solution composition of the present invention, the aromatic tetracarboxylic acid diester is dealcoholized by heating to become an acid anhydride, and this acid anhydride group reacts with an amino group. It is presumed that the reaction proceeds through a three-step reaction in which an amic acid group (amidic acid group) is formed and then dehydrated and closed to form an imide group.

  The organic polar solvent to be used is only required to dissolve the aromatic tetracarboxylic acid diester and the aromatic diamine, and it is preferable that the polyamic acid considered to be generated during imidization can be dissolved. Although not particularly limited, for example, N, N-dimethylformamide, N, N-dimethylacetamide, N, N-diethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-vinyl Amide solvents such as 2-pyrrolidone, cyclic ester solvents such as γ-butyrolactone, γ-valerolactone, δ-valerolactone, γ-caprolactone, ε-caprolactone, α-methyl-γ-butyrolactone, ethylene carbonate, propylene carbonate Carbonate solvents such as diethylene glycol, propylene glycol, triethylene glycol, etc., phenol solvents such as m-cresol, p-cresol, 3-chlorophenol, 4-chlorophenol, acetophenone, 1,3-dimethyl- 2-Imi Zorijinon, sulfolane, and dimethyl sulfoxide. The organic solvent to be used may be one type or two or more types. In the present invention, it is preferable to use an amide solvent, and it is also preferable to use a mixture with a glycol solvent if necessary.

  In the polyimide precursor solution composition of the present invention, the monomer concentration which is the total concentration of the aromatic tetracarboxylic acid diester and the aromatic diamine is preferably 10% by mass to 75% by mass, more preferably 20% by mass to 50%. % By mass. The solution viscosity at 30 ° C. when the monomer concentration is 20% by mass is preferably 0.1 Pa · s or less, more preferably 0.05 Pa · s or less, and particularly preferably 0.01 Pa · s or less. Is preferable in handling.

  If necessary, the polyimide precursor solution composition of the present invention may further include a chemical imidizing agent (for example, acid anhydrides such as acetic anhydride, amine compounds such as pyridine and isoquinoline, imidazole compounds), fillers (for example, Insulating fillers such as silica and alumina, conductive fillers such as carbon and metal particles, high thermal conductive fillers such as alumina, boron nitride and silicon nitride, dielectric fillers such as barium titanate)), dyes, pigments, silane cups A ring agent or the like can be added.

  In the present invention, the polyimide precursor solution composition is applied to a substrate and heated to form a polyimide film. A known method can be used for application to the substrate, but an inkjet method is preferred. By using the inkjet method, a polyimide film having a specific pattern can be formed on the substrate.

  The polyimide film is obtained by heat-treating a substrate coated with the polyimide precursor solution composition to remove the solvent and imidize (dehydrate ring closure). The heat treatment conditions are not particularly limited, but are generally 100 ° C. or higher, preferably 120 ° C. to 600 ° C., more preferably 150 ° C. to 500 ° C., still more preferably 150 ° C. to 400 ° C., preferably in steps. It is preferable to perform heat treatment for 0.01 to 30 hours, preferably 0.01 to 10 hours while increasing the temperature.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

A method for measuring the characteristics used in the following examples is shown below.
<Solution viscosity (rotational viscosity)>
It measured at 30 degreeC using the Tokimec E-type viscosity meter.
<Observation of coating state>
The state of the obtained coating layer was visually observed. Those that did not show turbidity and cracking, those that did not easily break even when folded, were good, and those that cracked and easily cracked when folded were considered bad.
<Heat expansion coefficient (CTE)>
Samples sampled to a length of 15 mm and a width of 4 mm were subjected to thermomechanical analysis at a tensile mode, a load of 4 gf, and a heating rate of 20 ° C./min using a Seiko Instruments SS6100. It was calculated from the TMA curve.
<Observation of change in viscosity over time>
After measuring the initial viscosity, it was stored at 25 ° C. for 30 days, and the viscosity was measured again.

The abbreviations of the compounds used in the following examples are described.
s-BPDA: 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride ODA: 4,4′-diaminodiphenyl ether PPD: p-phenylenediamine NMP: N-methyl-2-pyrrolidone PGL: propylene glycol EtOH : Ethanol 1,2-DMZ: 1,2-dimethylimidazole

[Example 1]
To a 500 mL glass reaction vessel equipped with a stirrer and a nitrogen gas introduction / discharge tube, 213 g of NMP was added as a solvent, and 147.11 g (0.50 mol) of s-BPDA and 55.28 g (1.2 mol) of ethanol were added thereto. Mol) and stirred at 80 ° C. for 10 hours to dissolve. To this solution, 40.05 g (0.20 mol) of ODA and 32.44 g (0.30 mol) of PPD were added and stirred at 50 ° C. for 3 hours to dissolve. To this solution, 48.8 g of 1,2-DMZ (10 wt% of the solution) was added to obtain a polyimide precursor composition having a monomer concentration of 40.9 mass% and a solution viscosity of 1.1 Pa · s.
This polyimide precursor composition was applied on a glass plate of a base material, and the temperature was 120 ° C. for 30 minutes, 150 ° C. for 10 minutes, 200 ° C. for 10 minutes, 250 ° C. for 10 minutes, and 400 ° C. A heat treatment was performed for 10 minutes to obtain a polyimide film having a thickness of 20 μm. About the obtained polyimide film, the state observation and thermal expansion coefficient (CTE) of the film were measured. The evaluation results are shown in Table 1.

[Example 2]
To a 500 mL glass reaction vessel equipped with a stirrer and a nitrogen gas introduction / discharge tube, 82 g of NMP and 82 g of PGL were added as solvents, and 147.11 g (0.50 mol) of s-BPDA and 55.28 g of ethanol (1 mol) .2 mol) was added and stirred at 80 ° C. for 10 hours to dissolve. To this solution, 40.05 g (0.20 mol) of ODA and 32.44 g (0.30 mol) of PPD were added and stirred at 50 ° C. for 3 hours to dissolve. To this solution, 43.9 g of 1,2-DMZ (10 wt% of the solution) was added to obtain a polyimide precursor composition having a monomer concentration of 45.5% by mass and a solution viscosity of 2.1 Pa · s.
This polyimide precursor composition was applied on a glass plate of a base material, and the temperature was 120 ° C. for 30 minutes, 150 ° C. for 10 minutes, 200 ° C. for 10 minutes, 250 ° C. for 10 minutes, and 400 ° C. A heat treatment was performed for 10 minutes to obtain a polyimide film having a thickness of 20 μm. With respect to the obtained polyimide coating, the state observation of the coating and the thermal expansion coefficient were measured. The evaluation results are shown in Table 1.

Example 3
NMP80g and PGL80g are added as a solvent to a glass reaction vessel having an internal volume of 500 mL equipped with a stirrer and a nitrogen gas introduction / discharge tube, and s-BPDA 147.11 g (0.50 mol), ethanol 55.28 g (1 .2 mol) was added and stirred at 80 ° C. for 10 hours to dissolve. To this solution, 30.04 g (0.15 mol) of ODA and 37.85 g (0.35 mol) of PPD were added and dissolved by stirring at 50 ° C. for 3 hours. To this solution, 43.0 g of 1,2-DMZ (for 10 wt% of the solution) was added to obtain a polyimide precursor composition having a monomer concentration of 45.5% by mass and a solution viscosity of 3.0 Pa · s.
This polyimide precursor composition was applied on a glass plate of a base material, and the temperature was 120 ° C. for 30 minutes, 150 ° C. for 10 minutes, 200 ° C. for 10 minutes, 250 ° C. for 10 minutes, and 400 ° C. A heat treatment was performed for 10 minutes to obtain a polyimide film having a thickness of 20 μm. With respect to the obtained polyimide coating, the state observation of the coating and the thermal expansion coefficient were measured. The evaluation results are shown in Table 1.

[Comparative Example 1]
192 g of NMP was added as a solvent to a glass reaction vessel having an internal volume of 500 mL equipped with a stirrer and a nitrogen gas introduction / discharge tube, and s-BPDA 132.40 g (0.45 mol), ethanol 49.76 g (1.08) were added thereto. Mol) and stirred at 80 ° C. for 10 hours to dissolve. To this solution, 36.04 g (0.18 mol) of ODA and 29.20 g (0.27 mol) of PPD were added, and the mixture was stirred and dissolved at 50 ° C. for 3 hours. The monomer concentration was 45.0 mass% and the solution viscosity was 1.7 Pa · s. The polyimide precursor composition was obtained.
This polyimide precursor composition was applied on a glass plate of a base material, and the temperature was 120 ° C. for 30 minutes, 150 ° C. for 10 minutes, 200 ° C. for 10 minutes, 250 ° C. for 10 minutes, and 400 ° C. A heat treatment was performed for 10 minutes to obtain a polyimide film having a thickness of 20 μm. About the obtained polyimide film, the state of the film was observed. The evaluation results are shown in Table 1.

[Reference Example 1]
To a 500 mL glass reaction vessel equipped with a stirrer and a nitrogen gas introduction / discharge tube, 198 g of NMP was added as a solvent, and 117.70 g (0.40 mol) of s-BPDA and 44.23 g (0.96) of ethanol were added thereto. Mol) and stirred at 80 ° C. for 10 hours to dissolve. To this solution, 48.06 g (0.24 mol) of ODA and 17.30 g (0.16 mol) of PPD were added, and the mixture was stirred and dissolved at 50 ° C. for 3 hours. The monomer concentration was 43.0% by mass, and the solution viscosity was 0.7 Pa · s. The polyimide precursor composition was obtained.
This polyimide precursor composition was applied on a glass plate of a base material, and the temperature was 120 ° C. for 30 minutes, 150 ° C. for 10 minutes, 200 ° C. for 10 minutes, 250 ° C. for 10 minutes, and 400 ° C. A heat treatment was performed for 10 minutes to obtain a polyimide film having a thickness of 20 μm. With respect to the obtained polyimide coating, the state observation of the coating and the thermal expansion coefficient were measured. The evaluation results are shown in Table 1.

[Reference Example 2]
To a 500 mL glass reaction vessel equipped with a stirrer and a nitrogen gas introduction / discharge tube, 198 g of NMP was added as a solvent, and 117.70 g (0.40 mol) of s-BPDA and 44.23 g (0.96) of ethanol were added thereto. Mol) and stirred at 80 ° C. for 10 hours to dissolve. ODA48.06g (0.24mol) and PPD17.30g (0.16mol) were added to this solution, and it stirred for 3 hours and was made to melt | dissolve at 50 degreeC. To this solution, 42.6 g of 1,2-DMZ (10 wt% of the solution) was added to obtain a polyimide precursor composition having a monomer concentration of 39.1% by mass and a solution viscosity of 0.6 Pa · s.
This polyimide precursor composition was applied on a glass plate of a base material, and the temperature was 120 ° C. for 30 minutes, 150 ° C. for 10 minutes, 200 ° C. for 10 minutes, 250 ° C. for 10 minutes, and 400 ° C. A heat treatment was performed for 10 minutes to obtain a polyimide film having a thickness of 20 μm. With respect to the obtained polyimide coating, the state observation of the coating and the thermal expansion coefficient were measured. The evaluation results are shown in Table 1.

Claims (4)

A polyimide precursor solution composition comprising an aromatic tetracarboxylic acid component comprising an aromatic tetracarboxylic acid diester and an aromatic diamine component,
The aromatic tetracarboxylic acid component is composed of 3,3 ′, 4,4′-biphenyltetracarboxylic acid diester in an amount of 50 mol% or more,
The aromatic diamine component contains p-phenylenediamine and 4,4′-diaminodiphenyl ether, and the proportion of paraphenylenediamine in the aromatic diamine component is 50 mol% or more,
A polyimide precursor solution composition comprising imidazoles. The polyimide precursor solution composition according to claim 1, wherein the solution viscosity is 0.01 Pa · s or less when the concentration of the polyimide precursor composed of the aromatic tetracarboxylic acid component and the aromatic diamine component is 20 mass%. object. The manufacturing method of the polyimide film which apply | coats the polyimide precursor solution composition in any one of Claim 1 or 2 to a base material, and imidizes by heating. The manufacturing method of the polyimide film of Claim 3 which apply | coats a polyimide precursor solution composition by the inkjet method.