JPS5952897B2 - Manufacturing method of polyimide precursor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a polyimide precursor by a polymerization reaction between an organic tetracarboxylic acid component and a diamine.

In recent years, a series of new polymers called heat-resistant polymers have been employed in the field of industrial materials that require heat resistance, chemical resistance, mechanical properties, and excellent electrical insulation properties.

Among these heat-resistant polymers, polyimide polymers in particular are used in a wide range of applications, including enamel wire coatings, films for copper-clad printed circuit boards, insulating films and sheets, adhesives, and cloth impregnated materials. It exhibits excellent characteristics. However, such polyimide polymers have a problem of poor adhesion to objects to be adhered such as various glasses, ceramics, and silicon wafers.

This can be understood from the fact that, for example, a method for producing polyimide film involves casting a solution of polyamic acid on a glass plate, drying it, and then peeling it off from the glass plate. For this reason, when polyimide polymers are used as coating materials for these objects to be adhered, it has been difficult to take advantage of the excellent properties inherent in the polymers. Therefore, in order to improve such adhesion, a functional silane compound is applied to a polyamic acid obtained by reacting an organic tetracarboxylic dianhydride and a diamine to activate the intramolecular or molecular chain terminal of the polyamic acid polymer. Attempts have been made to bond silane compounds via groups (free carboxyl groups, active hydrogen, amino groups, acid anhydride groups, etc.).

Although this silane-modified polyimide precursor improves adhesion to glass etc. to some extent, a large amount of functional silane compound must be used in order to impart adhesion to an industrially effective level. No. The reason for this is that since the reaction is between a long-chain polymer and a silane compound, the entire amount of the phosphorane compound, which has relatively low reactivity, does not necessarily work effectively. This is because a large amount is required.

This excess silane compound volatilizes during polyimide conversion and does not contribute at all to improving the adhesion, or causes a decrease in the excellent properties inherent to the polyimide polymer, such as moisture resistance. As a result of intensive studies from this point of view, the inventors created a silane-modified polycarboxylic acid component in which a part of the organic tetracarboxylic acid component was modified in advance with a specific functional silane compound, and this By polymerizing the diamine together with the acid component, reactivity, adhesion and polyimide properties can be improved. It was discovered that good results could be obtained for both of the inherent properties of Mido, and this led to the completion of this invention.

That is, in producing a polyimide precursor by a polymerization reaction of an organic tetracarboxylic acid component and a diamine, this invention preliminarily converts a portion of the carboxylic acid component into the following general formula (1); (wherein R is A divalent organic group containing a carbon atom directly bonded to a silicon atom; group, silyl group, siloxy group, disilanyl group, organosilyl group, organosiloxy group, organohalosilyl group and organohalosiloxy group),
The amino group (NH2) in the above general formula is reacted with at least one hydrolyzable group (X) to form the following general formula (2); (wherein, TOl is an organic tetracarboxylic acid component. a monovalent residue of TO2, a divalent residue of an organic tetracarboxylic acid component, Z is an acid group that may contain an x group bonded to a carbonyl carbon, R, X and Y are represented by the above general formula (1)
, where n is an integer of 2 or 3 if Y is an alkoxy group, acetoxy group or phenoxy group, or an integer of 2 if Y is a group other than the above). The present invention relates to a method for producing a polyimide precursor, which is characterized in that the carboxylic acid component is used as a carboxylic acid component, and the carboxylic acid component is polymerized with a diamine together with the remaining organic tetracarboxylic acid component.

In this way, in this invention, the silane-modified polycarboxylic acid component represented by the general formula (2) modified with various aminosilane compounds is polymerized with diamine as one of the organic tetracarboxylic acid components. This method is attractive because it provides higher reactivity than the conventional method of reacting a functional silane compound after synthesizing a polyimide precursor, and it also allows silane bonds to be inserted directly into the molecular core of the polyimide precursor. The sexual improvement effect will also be greater.

Adhesion that is recognized as industrially effective for bonding can be achieved with a small amount of the aminosilane compound, and therefore there is no concern that the moisture resistance of the polyimide polymer will be impaired. Moreover, when the polyimide precursor produced by this method is finally converted into polyimide by high-temperature heat treatment, it has excellent adhesion to glass, ceramics, silicon wafers, metal oxides such as aluminum oxide, etc. It exhibits excellent original heat resistance, chemical resistance, electrical insulation, mechanical properties, etc., and there is no particular need to further blend an unmodified ordinary polyimide precursor with the above-mentioned modified precursor. .

That is, according to the present invention, the above-mentioned excellent properties are exhibited by a simple operation of simultaneously polymerizing various silane-modified polycarboxylic acid components represented by the general formula (2) and a normal organic tetracarboxylic acid component with a diamine. Since it is possible to produce a polyimide precursor that has the following properties, it is extremely advantageous in terms of the production process, and homogenization of the polyimide can also be achieved.

The organic tetracarboxylic acid component used in this invention has two pairs of one pair of two acid groups bonded to adjacent carbon atoms, that is, a total of four acid groups, and is aromatic, aliphatic, or alicyclic. tetracanolebonic acids or their esters, amides, halides, monoanhydrides,
Derivatives such as dianhydrides are broadly included.

The most preferred organic tetracarboxylic acid component is aromatic tetracarboxylic dianhydride. These acid components may be used alone or in combination of two or more. Specific examples of such organic tetracarboxylic acid components are not listed here, but representative examples of aromatic organic tetracarboxylic dianhydrides that are considered suitable include, for example, pyromellitic dianhydride, 3.3″4.4″-benzophenonetetracarboxylic dianhydride, 3.3″4.4
″-biphenylcarboxylic dianhydride, 2, 3, 3″, 4
″-biphenyltetracarboxylic dianhydride, 2, 3, 6
・7 Naphthalenetetracarboxylic dianhydride, 1.2.
5,6-naphthalenetetracarboxylic dianhydride, 1,4
・5,8-naphthalenetetracarboxylic dianhydride, 2.
2-bis(3,4-dicarboxyphenyl)propanihydride, bis(3,4-dicarboxyphenyl)sulfone dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, bis( 3,4-dicarboxyphenyl)
2,2-bis(2,3-dicarboxyphenyl)propananhydride, 1,1-bis(2,3
-dicarboxyphenyl) ethanide anhydride, 1,1-bis(3,4-dicarboxyphenyl)ethane dianhydride,
Benzene-1,2,3,4-tetracarboxylic dianhydride, 2,3,6,7-anthracenetetracarboxylic dianhydride, 1,2,7,8-phenanthrenetetracarboxylic dianhydride and so on.

The silane-modified polycarboxylic acid component represented by the general formula (2) used in this invention is a part of the above-mentioned organic tetracarboxylic acid component expressed by the following general formula (1);
However, in the formula, R is a divalent organic group containing a carbon atom directly bonded to a silicon atom, x is a hydrolyzable group selected from an alkoxy group, an acetoxy group, a phenoxy group, and a halogen, and Y is an alkyl group, an alkoxy group, acetoxy group, phenoxy group, silyl group, siloxy group, disilanyl group, organosilyl group, organosiloxy group, organohalosilyl group, and organohalosiloxy group). That's what happens.

A typical example of the above aminosilane compound is the following molecular formula: H2NCH2CH(NH2)CH2Si
It is expressed as (0C0CH3)3.

Of course, it can be widely used as long as it satisfies general formula (1) other than the above. The modification reaction is a reaction between the amino group (NH2) and at least one hydrolyzable group x in general formula (1) and the organic tetracarboxylic acid component. Approximately 2 moles of the organic detracarboxylic acid component is used. The reaction usually proceeds exothermically, but it is usually carried out in the presence of a polar solvent such as N-methyl-2-pyrrolidone or N-N''-dimethylacetamide while cooling the reaction vessel using a water bath and controlling the temperature to below 30°C. The reaction may be carried out until the reaction system becomes homogeneous and transparent.Specific examples of silane-modified polycarboxylic acid components obtained by this method include pyromellitic dianhydride as an organic detracarboxylic acid component, and aminosilane as an organic detracarboxylic acid component.
H2 as a compound
NCH2CH2NHCH2CH2CH2CH2Si(0
The structural formula for an example using CH3)3 is as follows. In addition, in the following structural formula (1), the expressions in parentheses mean each structural part shown in general formula (2). In the above structural formula (1), in order to set n = 3, approximately 3 moles of pyromellitic dianhydride may be used per 1 mole of the aminosilane compound, and in order to set n = 2, 1 mole of the aminosilane compound may be used. Approximately 2 moles of pyromellitic dianhydride may be used.

Depending on the number of moles of pyromellitic dianhydride used, the composition may include a mixture of n:2 and n=3, but in this invention, such a mixed state is used. There is no problem even if it is. On the other hand, the above example uses an aminosilane compound whose general formula (1) is an alkoxy group, but an aminosilane compound in which Y is an alkoxy group or a group other than an acetoxy group or a phenoxy group is used. When doing so, the number of moles of the organic detracarboxylic acid component used per 1 mole of the aminosilane compound must be approximately 2 moles, and a silane-modified polycarboxylic acid component such that n in general formula (2) is 2 must be produced. .

By leaving at least one alkoxy group, acetoxy group, halogen, or phenoxy group directly bonded to a silicon atom in the modified carboxylic acid component, the adhesion to glass etc. when made into a polyimide polymer can be significantly improved. Furthermore, when a dianhydride is used as the organic tetracarboxylic acid component as in the above example, the In the example below, CH3
O group) is included.

On the other hand, when an organic tetracarboxylic acid component other than dianhydride is used, for example, one containing four free carboxyl groups, or one in which some or all of them are esterified, amidated or halogenated, etc. General formula (2
Oki's Z structural part is usually composed of the above-mentioned acid group itself, and in some cases, it may have a structure similar to that of the dianhydride, in which this acid group and the x group that has undergone an elimination reaction are reactively bonded. Furthermore, in each of these embodiments, when the Z structural moiety becomes an acid group other than a free carboxyl group, it may eventually be converted to a carboxyl group if some moisture is present in the system. In this invention, the silane-modified polycarboxylic acid component produced in this manner and the remaining unmodified polycarboxylic acid component are used. A polyimide precursor is produced by simultaneously polymerizing an organic tetracarboxylic acid component and a diamine.

Here, the ratio of the acid component to the diamine is preferably such that the amount of dialmine is equivalent to the total amount of the silane-modified polycarboxylic acid component and the unmodified organic tetracarboxylic acid component. However, if it is about a few percent, it is also possible to set the proportion so that the acid component represented by the above-mentioned total amount is in excess. The ratio of the silane-modified polycarboxylic acid component, which is one of the acid components, is the aminosilane compound used in the synthesis of this acid component, the organic tetracarboxylic acid component used in the above synthesis, and the unmodified organic tetracarboxylic acid component. The aminosilane compound may be present in an amount of 0.1 to IlO mol %, particularly preferably 0.3 to 2.0 mol %, based on the total number of moles of the raw material used consisting of the components and diamine.

According to the present invention, even if the amount of the aminosilane compound is reduced as mentioned above, a sufficiently satisfactory effect of improving adhesion to glass etc. can be obtained. On the other hand, if the amount exceeds the above, the moisture resistance of the polyimide that is finally formed may be impaired, and the electrical properties such as film properties (tensile strength and toughness when formed into a film) and dielectric strength voltage may be deteriorated. Not desirable. Diamines used in polymerization reactions include aromatic diamines,
Both aliphatic diamines and alicyclic diamines can be used.

In order to exhibit better heat resistance, it is preferable to use aromatic diamines. These diamines may be used alone or in combination of two or more. Although there is no need to list specific examples of such diamines, typical examples of aromatic diamines that are considered suitable include metaphenylene diamine, paraphenylene diamine, 4,4''-diaminodiphenyl, etc. Methane, 4.
4″-diaminodiphenyl ether, 2,2″-bis(
4-aminophenyl) propane, 3,3''-diaminodiphenylsulfone, 4,4''-diaminodiphenylsulfone, 4,4''-diaminodiphenyl sulfide, benzidine, benzidine-3,3''-dicanolebonic acid, benzidine -3,3'-disulfonic acid, benzidine -3-monocanolebonic acid, benzidine -3-monosulfonic acid, 3.
Examples include 3''-dimethoxybenzidine, para-bis(4-aminophenoxy)benzene, meta-bis(4-aminophenoxy)benzene, metaxylylenediamine, paraxylylenediamine, and the like.

The polymerization reaction may be carried out according to a conventionally known method, and is generally carried out in the presence of an organic solvent while controlling the temperature at 60°C or lower, preferably 30°C or lower, until a high degree of polymerization is obtained. Just let it happen.

This degree of polymerization can be easily detected by examining the intrinsic viscosity [η] of the reactant. As an organic solvent,
For example, N-methyl-2-pyrrolidone, N-N''-dimethylacetamide, N-N''-dimethylformamide,
Highly polar basic solvents such as N・N''-dimethyl sulfoxide and hexamethylphosphoramide are used. All of these types of solvents are highly hygroscopic, and the absorbed water causes a decrease in molecular weight during polymerization and storage. It is recommended to thoroughly dehydrate with a dehydrating agent before use, as this may cause a decrease in stability.Also, along with these solvents, toluene, xylene,
General-purpose solvents such as benzonitrile, benzene, and phenol can also be used in combination. However, the amount used should be within a range that does not reduce the solubility of the polyimide precursor produced. The polyimide precursor of the present invention obtained in this manner mainly consists of a polymer structural part consisting of an unmodified organic tetracarboxylic acid component as shown in the following structural formula (2) and a silane-modified polycarboxylic acid component. It has a structure in which the polymer structural parts are combined in a predetermined ratio, or it has a polymer structure in which an unmodified organic tetracarboxylic acid component and a silane-modified polycarboxylic acid component are randomly polymerized with diamino. It is also characterized by having a silane bond in the molecular core of the polyimide precursor. In addition, these modified polyimide precursors may further contain a polyimide precursor consisting of a partially unmodified organic tetracarboxylic acid or a silane-modified polycarboxylic acid component alone.The following structural formula (2) is Pyromellitic dianhydride as the organic tetracarboxylic acid component,
4,4''-diaminophenyl ether is used as the diamine, and the above-mentioned tetracarboxylic acid component is modified with an aminosilane compound to form a silane-modified polyvalent carboxylic acid component represented by the above-mentioned structural formula (1) ( However, an example of a polyimide precursor in the case where n=2) is used is shown.

According to such a polyimide precursor, by applying it to an adherend and then subjecting it to high temperature heat treatment, excellent adhesion or adhesion can be achieved even if the adherend is various types of glass, ceramics, silicon wafers, metal oxides, etc. This polyimide can be converted into a polyimide that exhibits properties such as good heat resistance, chemical resistance, mechanical properties, and excellent electrical insulation properties.

Therefore, the polyimide precursor obtained by the method of this invention has the advantage that it can be applied not only to various conventionally known uses, but also as a coating material for various glasses, ceramics, silicon wafers, etc.

Examples of this invention will be described below.

In the following, the intrinsic viscosity [η] is used as a parameter indicating the degree of polymerization (molecular weight) of the polyimide precursor. It was determined according to the following formula at °C (constant temperature bath). [η]=1n(t/TO
)/Ct; fall time of polymer solution measured with Ubbelohde viscometer.

TO: Falling time of the solvent measured in the same manner as above.

C; Polyimide precursor (polymer) concentration (4). 5% polymerization). Example 1 50 with a stirring device, cooling pipe, thermometer, and nitrogen purge device
A 0ml flask was fixed on a water bath.

288.63 g of purified N-methinoto-2-pyrrolidone, which had been dried over phosphorus pentoxide for a day and night and further distilled under reduced pressure, was added to the flask, and nitrogen was flushed into the flask. Next, γ-ureidopropyltriethoxysilane [H2NCONHCH2CH
50% by weight methanol solution of 2CH2Si(0CH2CH3)3 (4) Product name: A-116
0) Add 1.584g (0.003mol), then 3
- 1.764 g (0.006 mol) of 3'', 4,4''-biphenynoretetracanolebonic dianhydride was gradually added.

After this addition, the temperature of the reaction system rose, but the reaction temperature was controlled to be 30° C. or lower using a water bath. A silane-modified polycarboxylic acid was synthesized by reacting until the reaction system became transparent. Next, add 4.4″-
Diaminodiphenyl ether 20.0g (0.1 mol)
Add and dissolve completely, then add 3.3", 4.4"-
Biphenyltetracarboxylic dianhydride 28.518g (
0.097 mol) was added and stirred until the reaction system became a clear viscous solution.

Although the temperature rose during this operation, it was maintained at 30° C. or lower due to water dissolution. The polyimide precursor thus obtained had an intrinsic viscosity of 1.54.

This precursor solution was casted on a glass plate and dried at 150°C for 1 hour and at 200°C for 1 hour in a hot air dryer.
It was converted into polyimide by heating at ℃ for 6 hours. The formed polyimide film was strong and had good adhesion to glass under normal conditions. It was also found that the adhesive did not peel off even in a pressure vacuum test (hereinafter abbreviated as PCT) at 121° C. and 2 atm, indicating that the adhesion was highly improved. For reference, in the above examples, the number of moles of γ-ureidopropyltriethoxysilane used in the synthesis of the silane-modified polycarboxylic acid component was 0.03 monole, 3.3".
The number of moles of 4,4''-biphenynoretetracarboxylic dianhydride is changed to 0.06 moles, and unmodified 3,3 is reacted with the diamine together with this modified polyhydric carboxylic acid component.
A polyimide precursor solution was prepared in the same manner as described above except that the number of moles of ".4.4"-biphenyltetracarboxylic dianhydride was set to 0.07 moles.

The intrinsic viscosity of the polyimide precursor in this case was 0.41. When a polyimide film was formed using this precursor solution in the same manner as described above, the adhesion was good both in the normal state and by PCT. However, because the degree of polymerization of the polyimide precursor was too low, the film-forming ability and film toughness were poor, and the film had poor moisture resistance. Comparative Example 1 283.63 g of purified N-methyl-2-pyrrolidone was added to the same reaction vessel as in Example 1, and the mixture was heated to 4.4" under a nitrogen stream.
20.0 g (0.1 mol) of -diaminodiphenyl ether and 29.4 g (0.1 mol) of 3.3"-4.4"-biphenyltetracarboxylic dianhydride were gradually added.

The reaction system rose to 42°C, but was cooled to 30°C in a water bath and stirred until it became a transparent viscous bath liquid. 5 of the aminosilane compound used in Example 1 was added to this polyimide precursor solution.
0% methanol solution 1.584g (4). 003 mol) was gradually added and reacted.

The intrinsic viscosity of the precursor after reaction was 1.94. When a polyimide film was formed on a glass plate using this solution under the same conditions as in Example 1, it did not peel off from the glass plate under normal conditions, but it peeled off easily under PCT. Comparative Example 2 279.93 g of purified N-methyl-2-pyrrolidone was added to the same reaction vessel as in Example 1, and the mixture was heated to 4.4" under a nitrogen stream.
-20.0 g (0.1 mol) of diaminodiphenyl ether and 29.4 g (a) of 3,3'',4,4''-biphenyltetracarboxylic dianhydride. 1 mol) was gradually added and stirred until a clear viscous solution was obtained.

The reaction system was cooled with water and controlled to be below 30°C. The intrinsic viscosity of the polyimide precursor after the reaction was 2.00. When a polyimide film was formed on a glass plate using this solution under the same conditions as in Example 1, the film was strong and had good flexibility, but it was only weakly adhered to the glass surface. It was easy to peel off, and it was completely peeled off in PCT.

Example 2 288.71 g of purified N-N''-dimethylacetamide was added to the same reaction vessel as in Example 1, and N-
β-(aminoethyl)γ-aminopropinolate
Remetokishiran [H2
NCH2CH2NHCH2CH2CH2Si(0CH3
) ３〕． (4) Manufactured by Unica Co., Ltd. Product name: A-11
20) 0.666 g (0.003 mol) was added, followed by gradual addition of 1.764 g (0.006 mol) of 3.3''/4.4'' biphenyltetracarboxylic dianhydride.

A silane-modified polycarboxylic acid component was synthesized by stirring the reaction system until it became transparent while controlling the temperature to be 30° C. or lower. Next, 20.0 g (4).1 mol) of 4.4''-diaminodiphenyl ether was added to this reaction system, and an additional 3.
28.518 g (0.097 mol) of 3'', 4, 4''-biphenyltetracarboxylic dianhydride was added, and the mixture was kept at 30°C. The mixture was stirred while stirring until a clear viscous solution was obtained. The polyimide precursor thus obtained has an intrinsic viscosity of 1
．． It was 61.

When a polyimide film was formed from this precursor solution in the same manner as in Example 1, the film had the same strong saddle properties and adhesion as in Example 1. Example 3 244.35 g of purified N-methyl-2-pyrrolidone was added to the same reaction vessel as in Example 1, and the reaction mixture of Example 2 was added under a nitrogen stream.
0.666g (0.003g) of the aminosilane compound used in
mol), followed by 1.3 mol of pyromellitic dianhydride.
08g (4). 006 mol) was added gradually.

While controlling the temperature of the reaction system to be 30° C. or lower, the mixture was stirred until a transparent solution was obtained, thereby synthesizing a silane-modified polycarboxylic acid component. Next, 20.0 g (a).1 mol) of 4,4''-diaminodiphenyl ether was added to this reaction system, and further 21.146 g (0.097 g) of pyromenoic dianhydride was added.
mol) and stirred while keeping the temperature below 30°C until a clear viscous solution was obtained.

The polyimide precursor thus obtained had an intrinsic viscosity of 1.28.

This precursor solution was casted on a glass plate and heated in a hot air dryer at 150°C for 1 hour and at 200°C for 1 hour.
It was converted into polyimide by heating at ℃ for 1 hour. The formed polyimide film was strong, had good adhesion both under normal conditions and by PCT, and no peeling from the glass plate was observed. Comparative Example 3 234.78 g of purified N-N''-dimethylacetamide was added to the same reaction vessel as in Example 1, and the mixture was heated for 4.4 hours under a nitrogen stream.
″-diaminodiphenyl ether 19.0g (0.09
21.80 g (4) of pyromellitic dianhydride while keeping the temperature below 30°C in a water bath. 1 mol) was gradually added and stirred until a clear viscous solution was obtained.

Adding 0.666 g (0.003 mol) of the aminosilane compound used in Example 2 to this polyimide precursor solution,
The reaction was stirred for 1 hour.

The intrinsic viscosity of the precursor after reaction was 0.58. When a polyimide film was formed using this precursor solution in the same manner as in Example 3, the flexibility and toughness of the film were inferior to that of Example 3, and the adhesion to glass was poor.
It was easily peeled off with T. Example 4 4.4″-diaminodiphenyl ether 20.0g (0
．． A polyimide precursor was prepared in the same manner as in Example 1, except that 19.8 g (a).1 mol) of 4.4''-diaminodiphenylmethane was used instead of 1 mol).

The intrinsic viscosity of this precursor was 1.17. When a polyimide film was formed using this precursor solution in the same manner as in Example 1, the film was slightly inferior in toughness compared to Example 1, but its adhesion to glass was the same. . Example 5 20.0 g of 4.4″-diaminodiphenyl ether (0
．． 1 mole) instead of 10.8 g of paraphenylenediamine
A polyimide precursor was prepared in the same manner as in Example 1, except that (0.1 mol) was used.

The intrinsic viscosity of this precursor was 1.64. When a polyimide film was formed using this precursor solution in the same manner as in Example 1, both the toughness and adhesion of the film were the same as in Example 1. Example 6 Instead of 28.518 g (0.097 mol) of unmodified 3,3″,4,4″-biphenyltetracarboxylic dianhydride that is polymerized with diamine together with the silane-modified polycarboxylic acid component, Pyromellitic dianhydride 10.573g
(0.0485 mol) and 14.259 g (0.04
A polyimide precursor was prepared in the same manner as in Example 1, except that a mixture with 85 mol) was used.

Claims (1)

[Claims] 1. When producing a polyimide precursor by the polymerization reaction of an organic tetracarboxylic acid component and a diamine, a part of the above carboxylic acid component is preliminarily converted into the following general formula (1); ▲ mathematical formula,
There are chemical formulas, tables, etc. ▼・・・・・・・・・・・・・
・・・・・・・・・(1) (In the formula, R is a divalent organic group containing a carbon atom directly bonded to a silicon atom, and X is selected from an alkoxy group, an acetoxy group, a phenoxy group, and a halogen. The hydrolyzable group, Y, is selected from an alkyl group, an alkoxy group, an acetoxy group, a phenoxy group, a silyl group, a siloxy group, a disilanyl group, an organosilyl group, an organosiloxy group, an organohalosilyl group and an organohalosilyl group. An aminosilane compound represented by the following general formula (2) is reacted with an amino group (NH_2) in the above general formula and at least one hydrolyzable group (X); ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(2) (In the formula, T_c_1 is a monovalent residue of an organic tetracarboxylic acid component, T_c_2 is a divalent residue of an organic tetracarboxylic acid component, and Z is a carboxyl group. An acid group that may contain an X group bonded to carbon, R, 3, Y is an integer of 2 in the case of a group other than the above), and this carboxylic acid component is polymerized with diamine along with the remaining organic tetracarboxylic acid component. A method for producing a polyimide precursor, the method comprising: