JPS5952898B2 - Method for producing 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 variety of fields, including enamel wire covering materials, films for copper-clad printed circuit boards, insulating films and sheets, adhesives, and cloth impregnation materials, and are known for their excellent properties. It exhibits certain characteristics. However, such polyimide polymers have a problem of poor adhesion to objects to be adhered such as various glasses, ceramics, silicon wafers, and the like.

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, in order to provide adhesion to an industrially effective level,
Large amounts of functional silane compounds must be used. 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 of denaturation is required.

This excess silane compound volatilizes during polyimide conversion, and either does not contribute to the improvement of adhesion at all, or becomes a cause of deterioration of 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 previously modified with a specific functional silane compound and an organic diisocyanate compound. By polymerizing this with diamine along with the remaining organic tetracarboxylic acid component, it was discovered that good results could be obtained in terms of reactivity, adhesion, and the inherent properties of polyimide, which led to the completion of this invention. It is.

That is, in producing a polyimide precursor by a polymerization reaction between 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); (In the formula, R1 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 a Aminosilane represented by a group selected from alkyl group, alkoxy group, acetoxy group, phenoxy group, silyl group, siloxy group, disilanyl group, organosilyl group, organosiloxy group, organohalosilyl group and organohalosiloxy group) compound and
The following general formula (2);0CN-R2NCO...(
2) Using an organic diisocyanate compound represented by (in the formula, R2 represents a divalent organic group), one pair of two acid groups (two pairs of covalent groups) are bonded to adjacent carbon atoms of the organic tetracarboxylic acid component. ) and the amino group of the aminosilane compound, and between the other acid group and the isocyanate group of the organic diisocyanate compound, and the remaining isocyanate group of the organic diisocyanate compound involved in this reaction is further reacted with an organic The following general formula (3) obtained by reacting a tetracarboxylic acid component; (However, in the formula, TC
4 is a tetravalent residue of an organic tetracarboxylic acid component, TCl is a monovalent residue of the same component, and R1, R2, x and Y are the same as in the above general formulas (1) and (2)) The present invention relates to a method for producing a polyimide precursor, which comprises a silane-modified polycarboxylic acid component represented by the following formula, and polymerization reaction of this carboxylic acid component with a diamine together with the remaining organic tetracarboxylic acid component.

As described above, in the present invention, a silane-modified polycarboxylic acid component represented by the general formula (3) modified with various aminosilane compounds and an organic diisocyanate compound is polymerized with a diamine as one of the organic tetracarboxylic acid components. As a result, higher reactivity can be obtained compared to the conventional method in which a functional silane compound is reacted after synthesizing a polyamic acid polymer. This can be achieved with a small amount of use, 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 inherently excellent 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 (3) 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.

In addition, apart from this invention, the inventors modified a part of the organic tetracarboxylic acid component only with the above-mentioned aminosilane compound, that is, modified the amino group of the aminosilane compound and at least one hydrolyzable group (X). We proposed a method for producing polyimide precursors in which a silane-modified polycarboxylic acid component is prepared by reacting each organic tetracarboxylic acid component, and this is polymerized with a diamine together with the remaining organic tetracarboxylic acid component.

This method is also an excellent manufacturing method that has a great effect of improving adhesion to glass, etc., but there was a tendency for the degree of polymerization to be slightly lower during the polymerization reaction. On the other hand, with the silane-modified polycarboxylic acid represented by the general formula (3) modified using an organic diisocyanate compound together with an aminosilane compound according to the method of this invention, the polymerization rate during the polymerization reaction is lower than that of the other invention. It has been confirmed that the advantages of increasing the polyimide strength are obtained, and that good results can be obtained depending on the properties of the polyimide that is finally formed.

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. Tetracarboxylic acids of the group or derivatives thereof such as esters, amides, halides, monoanhydrides, dianhydrides, etc. are widely 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. Although there is no need to list specific examples of such organic tetracarboxylic acid components, typical 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″-biphenyltetracarboxylic 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(3,4dicarboxyphenyl)propanihydride, Bis(3,4-dicanoleboxyphenyl)snorehon dianhydride, 3,4,9.10-perylenetetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl)ether dianhydride, 2. 2-bis (2・3
-dicarboxyphenyl)propanihydride, 1.1-
Bis(2,3-dicarboxyphenyl)ethane dianhydride, 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 the like.

The silane-modified polycarboxylic acid component represented by the general formula (3) used in this invention is obtained by modifying a part of the above-mentioned organic tetracarboxylic acid component with an aminosilane compound and an organic diisocyanate compound. However, the above-mentioned compounds used here are as follows.

First, the aminosilane compound has the following general formula (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. hydrolyzable group, Y
is a group 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 organohalosiloxy group)
It is expressed as

Typical examples of such aminosilane compounds include those represented by the following molecular formula.

Of course, it can be widely used as long as it satisfies general formula (1) other than the above. Further, the organic diisocyanate compound has the following general formula (2);0CN-R2-NCO...
(2) (wherein R2 represents a divalent organic group), and broadly includes aromatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates.

Further, blocked forms of these diisocyanates such as phenol and cresol can also be used. Most preferred are aromatic diisocyanates. Specific examples of such organic diisocyanate compounds include methane diisocyanate, butane-1,1-diisocyanate, butane-1,2-diisocyanate, ethane-1,2-diisocyanate, propane-1,3-diisocyanate, and butane-1,2-diisocyanate. 1,4-diisocyanate, pentane-1,5-diisocyanate, hexane-1,6
-diocyanate, heptane-1,7-diisocyanate, octane-1,8-diisocyanate, nonane-1
・Aliphatic diisocyanates such as 9-diisocyanate and decane-1,10-diisocyanate, ω・ω″-1
・3-dimethylcyclohexane diisocyanate, ω・
Alicyclic diisocyanates such as ω″-1,4-dimethylcyclohexane diisocyanate, dicyclohexane-1,3-diisocyanate, dicyclohexane-1,4-diisocyanate, dicyclohexylmethane-4,4″-diisocyanate, ω・ω″- 1,3-dimethylbenzene diisocyanate, ω・ω-1,4-dimethylbenzene diisocyanate, ω・ω″-1,4-dimethylnaphthalene diisocyanate, ω・ω-1,5-dimethylnaphthalene diisocyanate, 1,3-phene Nylene diisocyanate, 1,4-phenylene diisocyanate, 1-methylbenzene-2,4-diisocyanate, 1
-Methylbenzene-2,5-diisocyanate, 1-methylbenzene-2,6-diisocyanate, 1-methylbenzene-3,5-diisocyanate, diphenyl ether-4,4''-diisocyanate, diphenyl ether-2, 4″-diisocyanate, naphthalene-1・
4-diisocyanate, naphthalene-1,5-diisocyanate, biphenyl-4,4'-diisocyanate,
Aromatic diisocyanates such as diphenylmethane-4,4''-diisocyanate, diphenylsulfide-4,4''-diisocyanate, and diphenylsulfone-4,4''-diisocyanate are exemplified.

The first step of the modification reaction is a reaction between one of the two acid groups (two pairs) bonded to adjacent carbon atoms of the organic tetracarboxylic acid component and the amino group of the aminosilane compound, and this reaction In order to achieve this, approximately 2 moles of the aminosilane compound are used per 1 mole of the organic tetracarboxylic acid component.

The reaction usually proceeds exothermically, but it is generally controlled to below 30°C while cooling the reaction vessel using a water bath or the like in the presence of a polar solvent such as N-methyl-2-pyrrolidone or N-N''-dimethylacetamide. The reaction product obtained by the above reaction is conveniently referred to as the first modified intermediate.

This intermediate contains a reaction product (
As seen in 4), there are still unreacted acid groups. That is, the other of the two pairs of acid groups bonded to adjacent carbon atoms of the starting organic tetracarboxylic acid component is in an unreacted state. The following reaction formula (1), as a specific example of the first reaction, uses pyromellitic dianhydride as the organic tetracarboxylic acid component and H2NCH as the aminosilane compound.
An example using 2CH2NHCH2CH2CH2Si(0CH3)3 is shown. Here, the unreacted acid group of the product (A) is a carboxyl group. The second step of the modification reaction is a reaction between the unreacted acid groups contained in the first modification intermediate and the isocyanate groups of the organic diisocyanate compound. In other words, approximately 2 moles of the organic diisocyanate compound are used per 1 mole of the raw material organic tetracarboxylic acid.

The reaction is generally carried out under slightly warmed conditions, e.g. 65°C.
The reaction is carried out under moderate heating, and heating accelerates the reaction. The reaction product obtained by this reaction is conveniently referred to as a second modified intermediate. In this intermediate, as shown in reaction product (B) based on the following reaction formula (2), unreacted isocyanate groups are present in the organic diisocyanate compound that participated in the reaction. The following reaction formula (2) shows an example in which the product based on the reaction formula (1) and diphenylmethane to 4.4''-diisocyanate are used as the organic diisocyanate compound.The final stage of the modification reaction The step is a reaction between the free isocyanate group contained in the second modified intermediate and the acid group of another organic tetracarboxylic acid component, and through this reaction, the final target general formula (3) is obtained. This method synthesizes the silane-modified polycarboxylic acid shown below.

In this reaction, approximately 2 moles of the organic tetracarboxylic acid component are used per 1 mole of the second modified intermediate, in other words, 2 moles of the organic diisocyanate compound used in the second step.
The reaction is generally carried out under slightly warmed conditions, e.g. 65°C.
The reaction is carried out under moderate heating, and the reaction is accelerated by heating. Note that this final stage modification reaction may proceed simultaneously with the second stage modification reaction, if necessary.

That is, after the first stage modification reaction, the organic diisocyanate compound and the new organic tetracarboxylic acid component in the predetermined ratio may be simultaneously added and reacted continuously under the same heating conditions as described above while suppressing side reactions. It is possible. As is already clear from the above explanation, the silane-modified polycarboxylic acid component represented by the general formula (3) according to the present invention thus obtained is obtained by combining 3 moles of the organic tetracarboxylic acid component with 2 moles of the aminosilane compound and the organic tetracarboxylic acid component. It can be said to have been modified with 2 moles of a diisocyanate compound.

The following structural formula (1) shows an example in which the reaction product (B) as the second modified intermediate is further reacted with 2 moles of pyromellitic dianhydride.

In addition, in this structural formula (1), the representation within 0 is the general formula (3)
It means each structural part shown by. In the present invention, a polyimide precursor is produced by polymerizing the silane-modified polycarboxylic acid component thus produced and the remaining unmodified organic tetracarboxylic acid component simultaneously with diamine.

Here, the ratio of the acid component to the diamine is preferably such that the diamine 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 possible to set the proportion so that the acid component expressed by the above total amount is in excess. The proportion of the silane-modified polycarboxylic acid component used is usually 0.1 to 20% of the total weight of the acid component, unmodified organic tetracarboxylic acid component, and diamine.
The amount may be adjusted to 1% to 5% by weight, particularly preferably 1 to 5% by weight.

According to this invention, a sufficient effect of improving adhesion can be obtained by using the modified carboxylic acid, that is, the aminosilane compound, in a small amount as described above. Furthermore, if too much modified polyhydric carboxylic acid is used, the final polyimide formed,
This is undesirable because it may impair the moisture resistance of the film, film properties (tensile strength and toughness when formed into a film), and electrical properties such as dielectric strength voltage. Group 4 diamines, aliphatic diamines, and alicyclic diamines can all 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, 3,3
''-dimethyne-benzidine, para-bis(4-aminophenoxy)benzene, meta-bis(4-aminophenoxy)benzene, metaxylylene diamine, paraxylylene diamine, 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, N-
Highly polar basic solvents such as -N''-dimethyl sulfoxide and hexamethylphosphoramide are used. All of these types of solvents are highly hygroscopic, and the absorbed water reduces molecular weight during polymerization and stabilizes storage. It is recommended to thoroughly dehydrate the product with a dehydrating agent before use.General-purpose solvents such as toluene, xylene, benzonitrile, benzene, and phenol may also be used in conjunction with these solvents. 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 way is mainly composed of compounds as shown in the following structural formula (2). It has a structure in which a polymer structure consisting of an unmodified organic tetracarboxylic acid component and a polymer structure consisting of a silane-modified polyhydric carboxylic acid component are combined in a predetermined ratio, or a polymer structure consisting of an unmodified organic tetracarboxylic acid component and a silane-modified polymer structure is combined. It has a polymer structure in which a polycarboxylic acid component is randomly polymerized with a diamine, and both are characterized by having a structure in which a silane compound is bonded pendantly to the molecular chain of a polyimide precursor. The modified polyimide precursor may further contain a polyimide precursor consisting of a portion of an unmodified organic tetracarboxylic acid or a silane-modified polyhydric carboxylic acid alone.The following structural formula (2) is an organic tetracarboxylic acid component. As a silane-modified polyhydric carboxylic acid component obtained by using pyromellitic dianhydride as the diamine and 4,4''-diaminodiphenyl ether as the diamine, the above tetracarboxylic acid component is modified with an aminosilane compound and an organic diisocyanate compound. This figure shows an example of a polyimide precursor using the one represented by the above-mentioned structural formula (1).

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 its inherent 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 glass 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; falling time TO of the polymer solution measured with an Ubbelohde viscometer; falling time of the solvent measured in the same manner as above.

C: Polyimide precursor (polymer) concentration (0.5% by weight
). Example 1 50 with a stirring device, cooling pipe, thermometer, and nitrogen purge device
A 0ml flask was fixed on a water bath.

280.6 g of purified N-methyl-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 [H2NCONHCH2CH2
50% by weight methanol solution of CH2Si(0CH2CH3)3 (4) Manufactured by Hon Unica, trade name: A-1160)
Add 52.8d1 (0.1 mol), then add 3.3″.
4.4″-biphenyltetracarboxylic dianhydride 14.
7 g (0.05 mol) were added slowly.

After the addition, the temperature of the reaction system rose, so use a water bath to
The temperature was controlled to be below 0°C. After the reaction system becomes transparent, add 100 g of a 25% by weight solution of diphenylmethane-4,4''-diisocyanate in N-methyl-2-pyrrolidone.
(4). 1 mol) and 29.4 g (0.1 mol) of 3,3'', 4,4''-biphenyltetracarboxylic dianhydride were added. The reaction temperature was raised to 65° C. with gentle stirring, and the reaction was completed when the reaction system became transparent after about 4 hours. In this way, a 20% by weight solution of the silane-modified polycarboxylic acid component represented by general formula (3) was prepared. Next, 282.4 g of purified N-methyl-2-pyrrolidone was added to another 500 ml flask similar to the above, and 7.41 g of a 20% by weight solution of the silane-modified polycarboxylic acid component synthesized by the above method was added under a nitrogen stream. , 20.0 g (0.1 mol) of 4,4''-diaminodiphenyl ether and 29.4 g (0.1 mol) of 3,3'',4,4''-biphenyltetracarboxylic dianhydride were added. The reaction system was maintained at 30° C. or lower using a water bath and stirred until it became a transparent viscous solution.The polyimide precursor thus obtained had an intrinsic viscosity of 1.83.

A solution containing this precursor was casted on a glass plate and heated in a hot air dryer at 150°C for 1 hour, 200°C for 1 hour, and 250°C for 6 hours to convert it into polyimide.
The formed polyimide film was strong and had good adhesion to glass under normal conditions. Also, pressure tester test (hereinafter abbreviated as PCT) at 121℃ and 2 atmospheres.
However, it was found that there was no peeling and the adhesion was highly improved. For reference, in the above example, the weight of the 20% by weight solution of the silane-modified polycarboxylic acid component used during the polymerization reaction was changed to 54.34 g, and the polyimide precursor solution was otherwise prepared in the same manner as above. did.

The intrinsic viscosity of the polyimide precursor in this case was 0.55. 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 a clear viscous solution was obtained. 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.
- Gradually add 20.0 g (0.1 mol) of diaminodiphenyl ether and 29.4 g (0.1 mol) of 3,3", 4,4"-biphenyltetracarboxylic dianhydride,
Stir until a clear viscous solution is obtained.

The reaction system was cooled in a water bath 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 50% by weight of γ-ureidopropyltriethoxysilane
Instead of 52.8 g (0.1 mol) of methanol solution, N
-β-(aminoethyl)-γ-aminopropylene
Trimethoxysilane [H2NCH2CH2NHCH2CH2CH2Si(0
CH3) 3] (4) Manufactured by Hon Unika Co., Ltd. Product name: A-1
120) except that 22.2 g (0.1 mol) was used.
A 20% by weight solution of the silane-modified polycarboxylic acid component was prepared in exactly the same manner as in Example 1.

Further, using this solution, a polyimide precursor solution was prepared in the same manner as in Example 1. The intrinsic viscosity of the polyimide precursor at this time was 1.88. When a polyamide film was formed on a glass plate using the above polyimide precursor solution under the same conditions as in Example 1, the toughness and adhesion of the film were equivalent to those in Example 1.

Example 3 239.66 g of purified N·N'' dimethylacetumide was added to the same reaction vessel as in Example 1, and a 20% by weight solution of the silane-modified polycarboxylic acid component prepared in Example 2 was added under a nitrogen stream. 8.36 g, 20.0 g (0.1 mol) of 4.4''-diaminodiphenyl ether and 21.8 g (4) of pyromellitic dianhydride. 1 mol) was added.

The reaction system was kept at 30° C. or lower using a water bath, and stirring was continued until a transparent viscous solution was obtained. The polyimide precursor thus obtained had an intrinsic viscosity of 1.95.

A solution containing this precursor was casted on a glass plate and heated in a hot air dryer at 150°C for 1 hour, 200°C for 1 hour, and 300°C for 1 hour to convert it into polyimide. The formed polyimide film is tough, and is resistant to both normal and PC conditions.
Adhesion by T was good in all cases, and no peeling from the glass plate was observed. Comparison Example 3 234.16 g of purified N-N''-dimethylacetamide was added to the same reaction vessel as in Example 1, and 4.
4″-diaminodiphenyl ether 19.0g (0.0
95 mol) and 21.80 g (4) of pyromellitic dianhydride while keeping the temperature below 30°C in a water bath. 1 mole)
was gradually added and stirred until a clear viscous solution was obtained.

The aminosilane compound used in the synthesis of the silane-modified polycarboxylic acid component in Example 2 was added to this polyimide precursor solution.
．． 522 g (0.00235 mol) was added and the reaction was stirred for 1 hour.

The intrinsic viscosity of the precursor after reaction was 0.66. 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 1.35. 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
(stomach). A polyimide precursor was prepared in exactly the same manner as in Example 1, except that 1 mol) was used.

The intrinsic viscosity of this precursor was 1.72. Further, when a polyimide film was formed using a solution containing this precursor in the same manner as in Example 1, the toughness and adhesion of the film were both equivalent to those in Example 1. Example 6 4.4″-diaminodiphenyl ether 20.0g (0
．． A polyimide precursor was prepared in the same manner as in Example 2, except that 19.8 g (0.1 mol) of 4.4''-diaminodiphenylmethane was used instead of 1 mol).

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) (However, in the formula, R_1 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; Y is 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 aminosilane compound represented by the following general formula (2); OCN-
R_2-NCO...(2) (However, in the formula R_
2 represents a divalent organic group), one of the two acid groups (two pairs) bonded to adjacent carbon atoms of the organic tetracarboxylic acid component and the aminosilane compound. The reaction is carried out between the amino group and between the other acid group and the isocyanate group of the organic diisocyanate compound, and the remaining isocyanate group of the organic diisocyanate compound involved in this reaction is further reacted with an organic tetracarboxylic acid component. The following general formula (3); ▲There are mathematical formulas, chemical formulas, tables, etc.▼・
...(3) (However, in the formula, Tc_4 is a tetravalent residue of an organic tetracarboxylic acid component, Tc_1 is a monovalent residue of the same component, and R_1, R_2, X and Y are the above general formula (1),
(same as in the case of (2))), and this carboxylic acid component is polymerized with a diamine together with the remaining organic tetracarboxylic acid component. Production method.