JP2874014B2 - Curable resin composition and protective film for electronic component - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a curable resin composition obtained by blending a polyimide resin with a polyimide resin type compound having an alkoxysilyl group at a molecular terminal, which is suitably used as an insulating protective film for electronic parts. The present invention also relates to a composition obtained by dissolving the curable resin composition in an organic solvent, and a protective film for electronic parts comprising a cured product of the composition.

[0002]

2. Description of the Related Art Conventionally, a polyimide resin having excellent heat resistance, electrical and mechanical properties has been used as an insulating protective film for electronic parts and the like.
When forming a protective film, generally, a polyimide resin is insoluble in an organic solvent, so a solution of polyamic acid, which is a precursor thereof, is used, applied to a substrate, and then heated and cured to obtain a desired polyimide resin film. Is formed.

However, this conventional method using a polyamic acid solution is inferior in workability because the viscosity of the polyamic acid solution is extremely high, and requires a high temperature exceeding 300 ° C. for heat curing. The polyimide resin film is nickel, aluminum, silicon,
It has disadvantages such as poor adhesion to a substrate such as a silicon oxide film.

Among these drawbacks, the improvement of the adhesiveness to the substrate is described by a method using a polyimidesiloxane copolymer in which a part of a diamine component, which is a raw material of polyimide, is replaced with a diamine containing siloxane (Japanese Patent Publication No. Sho 43). -2
7439, JP-B-59-7213) or a method of mixing or reacting a silane having an amino group or an acid anhydride with a polyamic acid of a polyimide precursor (JP-B-58-32162, JP-B-58-1982). 321
No. 63, Japanese Patent Publication No. 1-29510, Japanese Patent Publication No. 61
-266436, and JP-B-61-207438).

However, in the former method, there is a problem that the heat resistance is lowered due to an increase in the siloxane content in the copolymer, and in the latter method, the storage stability of the solution is remarkably increased when the amount of silane added is increased. There is a problem of spoiling.

Further, those obtained by reacting a polyamic acid or a polyimide oligomer with an amino group-containing alkoxysilane (JP-A 56-157427, JP-A 56-157427)
157428, JP-A-60-240730 and JP-A-61-266436) have been proposed.

However, these methods also have a problem that the amount of silane added for storage stability and the like is limited.

In order to eliminate the heat treatment at a high temperature of 300 ° C. or more required for forming a polyimide film by curing a polyamic acid, a polyimide resin having a siloxane bond itself is dissolved in a solvent (Japanese Patent Publication No. Sho 61-8).
No. 3228, Japanese Patent Publication No. 61-118424, and Japanese Patent Publication No. 61-118425) have been proposed.

However, the polyimide resin films obtained by these methods are essentially inferior in solvent resistance and have problems in practical use.

The present invention has been made in view of the above circumstances, has good storage stability, can form a cured film at a low temperature, and has heat resistance, mechanical strength, electrical characteristics, solvent resistance, It is an object of the present invention to provide a polyimide resin-type curable resin composition that provides a cured film having excellent adhesiveness with a resin, and a protective film for electronic parts obtained by curing the cured resin composition.

[0011]

Means and Action for Solving the Problems The present inventors have
As a result of intensive studies to achieve the above object, polyimide 1 soluble in an organic solvent represented by the following structural formula (1) was obtained.
A polyimide resin-type curable composition comprising 1 part to 500 parts of a compound represented by the following structural formula (2) in 00 parts (% by weight, the same applies hereinafter) has excellent storage stability when dissolved in a solvent, and It can be easily cured by heating at a low temperature of 300 ° C or less to form a cured film having excellent heat resistance, mechanical strength, and electrical properties with good adhesiveness on a base material. The present invention has been found to be suitable for use as a protective film for electronic components and the like, and has led to the present invention.

[0012]

Embedded image And Y is an aromatic ring-containing diamine residue having 6 to 30 carbon atoms, and a siloxane having 2 to 20 silicon atoms, and a silicon diamine residue having a silethylene and silphenylene skeleton. The divalent group, p is an integer of 1 or more. )

[0013]

Embedded image (However, R ¹ and R ² have the same or different carbon atoms of 1
An unsubstituted or halogen- or alkoxy-substituted alkyl group, an alkenyl group and an aryl group, R ³ is an alkylene group having 1 to 9 carbon atoms,
An arylene group, an oxyalkylene group, an iminoalkylene group, a monovalent group selected from an oxyalkylenearylene group and an iminoalkylene group, Z is an aromatic ring containing 6 to 30 carbon atoms, a diamine residue, an aminophenol residue and A divalent group selected from aminocarboxylic acid residues, W is O or NH, and X and Y have the same meaning as described above. k is 0 or 1, m is an integer of 1 to 3, and n is an integer of 1 to 100. )

Accordingly, the present invention provides a curable resin composition containing 100 parts of the polyimide resin of the above formula (1) and 1 to 500 parts of the compound of the formula (2), and using the curable resin composition in an organic solvent. Disclosed are a curable resin composition which is dissolved and a protective film for electronic parts which is composed of a cured product of the curable resin composition.

Hereinafter, the present invention will be described in more detail. The polyimide resin-type curable resin composition of the present invention contains compounds of the following formulas (1) and (2).

[0016]

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Here, R ¹ and R ² are the same or different and are each a monovalent group having 1 to 10 carbon atoms and selected from an unsubstituted or halogen or alkoxy-substituted alkyl group, alkenyl group and aryl group; ³ is a monovalent group selected from an alkylene group, an arylene group, an oxyalkylene group, an iminoalkylene group, an oxyalkylenearylene group and an iminoalkylene group having 1 to 9 carbon atoms, and X contains an aromatic ring or an aliphatic ring. It is a tetravalent organic group and is derived from tetracarboxylic dianhydride described below. Y is an aromatic ring-containing diamine residue having 6 to 30 carbon atoms and 2 to 20 silicon atoms.
A divalent group selected from siloxane, silethylene and a silicon diamine residue having a silphenylene skeleton, Z
Is a divalent group selected from aromatic ring-containing diamine residues having 6 to 30 carbon atoms, aminophenol residues and aminocarboxylic acid residues, and W represents O or NH. k is 0 or 1, m
Is an integer of 1 to 3, and p is an integer of 1 or more. In order to obtain good workability, sufficient adhesive strength, and mechanical strength,
p is preferably 15 or more, and n is an integer of 1 to 100.

The polyimide resin (1) is reacted with a tetracarboxylic dianhydride of the following formula (3) and a diamine of the following formula (4) in an organic solvent according to a conventional method to obtain a polyamic acid. Can be obtained by dehydration condensation.

The compound (2) is a compound represented by the following formula (5) or (6) and an isocyanate silane (7)
Can be obtained by the reaction with

[0020]

Embedded image (However, R ¹ , R ² , R ³ , X, Y, Z, W, m, and n have the same meaning as described above.)

Here, X in the above formula is a tetravalent organic group containing an aromatic ring or an aliphatic ring, and is represented by the formulas (1) and (2).
Is derived from tetracarboxylic dianhydride which is a starting material of the polyimide represented by

[0022]

Embedded image It is methyldisiloxane.

X may be one of the above or a combination of two or more.

In the above formula, Y is a divalent organic group and is derived from diamine which is a starting material of the polyimides of formulas (1) and (2). This diamine is specifically p-phenylenediamine, m-phenylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-
Diaminodiphenyl ether, 2,2′-bis (4-amiphenyl) propane, 4,4′-diaminodiphenylsulfone, 4,4′-diaminodiphenylsulfide,
1,4-bis (3-aminophenoxy) benzene, 1,
4-bis (4-aminophenoxy) benzene, 1,4-
Bis (p-aminophenylsulfonyl) benzene, 1,
4-bis (m-aminophenylsulfonyl) benzene,
1,4-bis (p-aminophenylthioether) benzene, 1,4-bis (m-aminophenylthioether) benzene, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2- Bis [3-methyl-4- (4-aminophenoxy) phenyl] propane,
2,2-bis [3-chloro-4- (4-aminophenoxy) phenyl] propane, 1,1-bis [4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [3
-Methyl-4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [3-chloro-4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [3,5-
Dimethyl-4- (4-aminophenoxy) phenyl] ethane, bis [4- (4-aminophenoxy) phenyl]
Methane, bis [3-methyl-4- (4-aminophenoxy) phenyl] methane, bis [3-chloro-4- (4-
Aminophenoxy) phenyl] methane, bis [3,5-
Dimethyl-4- (4-aminophenoxy) phenyl] methane, bis [4- (4-aminophenoxy) phenyl]
An aromatic ring-containing diamine having 6 to 30 carbon atoms selected from sulfone and 2,2-bis [4- (4-aminophenoxy) phenyl] perfluoropropane, and a siloxane having 2 to 20 silicon atoms represented by the following formula: It is a silicon diamine having a silethylene and a silphenylene skeleton.

[0025]

Embedded image

Y may be one kind of the above-mentioned diamine residues or a combination of two or more kinds.

On the other hand, Z in the above formula is a divalent group selected from an aromatic ring-containing diamine residue having 6 to 30 carbon atoms, an aminophenol residue and an aminocarboxylic acid residue. The following formula (8), which is a starting material of (6),
It is derived from any of the diamines, aminophenols and aminocarboxylic acids represented by (9) and (10).

H ₂ N—Z—NH ₂ (8) H ₂ N—Z—OH (9) H ₂ N—Z—COOH (10)

The aromatic diamine is specifically the same as the diamine having an aromatic ring among the diamines represented by H ₂ N—Y—NH ₂ of the formula (4), and as described above. It is. Aminophenol is p-aminophenol or m-aminophenol, and aminocarboxylic acid is p-aminobenzoic acid, m-aminobenzoic acid or o-aminobenzoic acid.

On the other hand, a compound of the following formula (7) is used as the silicon compound.

[0031]

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Here, R ¹ and R ² are alkyl groups such as methyl group, ethyl group, propyl group and butyl group, alkenyl groups such as vinyl group, allyl group and butenyl group, and aryl groups such as phenyl group and tolyl group. Or a chloromethyl group, a chloropropyl group, a 3,3,3-trifluoropropyl group, a methoxy group, an ethoxyethyl group in which part or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with a halogen atom or an alkoxy group The same or different unsubstituted or substituted monovalent hydrocarbon groups having 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms, selected from
^{As 1} , an alkyl group or an alkoxy-substituted alkyl group is preferable, and as R ² , an unsubstituted or substituted alkyl group or an aryl group is suitably used.

[0033]

Embedded image Examples thereof include an alkylene arylene group (provided that,
In the above formula, p and q each represent an integer of 1 to 3).

Specific examples of the silicon compound represented by the formula (5) are as follows, but are not limited thereto. In the present invention, one of these silicon compounds can be used alone or in combination of two or more.

[0035]

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Here, among the compounds of the formula (2), k is 1
The compound of the following formula (2 ′) can be obtained by reacting the polyimide of the above formula (5) with the isocyanatosilane of the above formula (7). Note that the above equation (5)
Is a tetracarboxylic acid of formula (3) (n +
1) reacting n diamines of the formula (4) with two aromatic diamines or aminophenols of the formula (8) or (9) to obtain a polyamic acid, which is dehydrated according to a conventional method. Can be obtained by

[0037]

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When the curable resin represented by the above formula (2 ') is obtained by reacting the polyimide represented by the above formula (5) with the silicon compound represented by the above formula (7), the reaction is carried out with an organic solvent. Do inside. Examples of the organic solvent include N-methyl-2-pyrrolidone, dimethylacetamide, dimethylformamide, hexamethylphosphoramide, tetrahydrofuran, 1,4-dioxane, methylcellosolve, butylcellosolve, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and triethylene glycol dimethyl ether. , Acetone, methyl ethyl ketone, methyl isobutyl ketone,
Cyclopentanone, cyclohexanone, toluene, xylene and the like can be mentioned, and one of these can be used alone or in combination of two or more.

In the reaction, the molar ratio [(7) / (5)] between the silicon compound represented by the formula (7) and the polyimide compound represented by the formula (5) is in the range of about 1.9 to 2.1. The reaction temperature is preferably -20 ° C to 10 ° C.
0 ° C, especially 0 ° C to 80 ° C, is preferred. The reaction time is usually 0.5 to 10 hours. This reaction may be carried out without a catalyst or using a catalyst. As the catalyst, tertiary amine compounds, for example, triethylamine, ethylenediamine,
Benzyldimethylamine and the like.

The curable resin composition of the present invention uses the compound of the formula (2) in a proportion of 1 to 500 parts, more preferably 5 to 300 parts, per 100 parts of the polyimide of the above formula (1). The combined use of the compounds of the formulas (1) and (2) has the characteristic that the compounds of the formulas (1) and (2) are superior in adhesiveness, solvent resistance and mechanical properties as compared with the case where the compounds are used alone. Have.

The curable resin composition can be dissolved in an organic solvent and used as a curable resin solution composition. As the organic solvent used at this time, any solvent can be used as long as it can dissolve the curable resin composition, but from the viewpoint of workability and the like, amides, ethers, cellosolves, and ketones are more preferable. Specifically, N-methyl-2-pyrrolidone, dimethylacetamide, dimethylformamide, hexamethylphosphoramide, tetrahydrofuran, 1,4-dioxane, methyl cellosolve, butyl cellosolve, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, triethylene Glycol dimethyl ether,
Acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone and the like can be mentioned, and one of these can be used alone or two or more can be used in combination.

The solution obtained by dissolving the curable resin composition represented by the formulas (1) and (2) in these solvents is usually heated at a temperature of 100 ° C. or higher, preferably 150 ° C. or higher for 1 to 10 hours. The cross-linking reaction of the alkoxysilyl group proceeds due to moisture in the atmosphere or in the atmosphere, and is cured, and has excellent heat resistance including imide groups, mechanical properties, and electrical properties,
In addition, a high molecular weight polymer excellent in adhesiveness to a substrate and solvent resistance can be easily obtained.

Accordingly, the curable resin of the present invention can be prepared by various methods using various base materials, for example, a semiconductor device, specifically, a passivation film, a protective film, a diode,
Junction protection film for junctions such as transistors, VL
In addition to SI α-ray shielding films, interlayer insulating films, ion implantation masks, etc., conformal coats for printed circuit boards, alignment films for liquid crystal display elements, protective films for glass fibers, surface protective films for solar cells, and various fillers Can be used over a wide range, such as an insulating paste material for printing containing, and a conductive paste material containing a conductive material.

[0044]

As described above, the curable resin composition of the present invention has good storage stability in a solution dissolved in a solvent, and has good heat resistance, mechanical strength, electrical properties, and solvent resistance. A good cured film can be formed at a low temperature of 300 ° C. or less with good adhesiveness to the substrate.

[0045]

The present invention will be described in detail with reference to the following examples, but the present invention is not limited to the following examples. Prior to the examples, production examples of the polyimide of the formula (1) and the compound of the formula (2) used in the following examples are shown as reference examples.

REFERENCE EXAMPLE 1 22.2 g (0.05 mol) of 2,2-bis (3,4-benzenedicarboxylic acid anhydride) perfluoropropane was placed in a flask equipped with a stirrer, a thermometer and a nitrogen purge device. 200 g of N-methyl-2-pyrrolidone was charged as a solvent, and 80 g of a N-methyl-2-pyrrolidone solution in which 10.0 g (0.05 mol) of diaminodiphenyl ether was dissolved was gradually added dropwise. After completion of the dropwise addition, the mixture was further stirred at room temperature for 10 hours. Then, a reflux condenser with a water receiver was attached to the flask, 30 g of xylene was added, the temperature of the reaction system was raised to 160 ° C., and the temperature was maintained for 6 hours. . By this reaction, 1.3
g of water was produced.

After cooling the yellow-brown reaction solution obtained by the above operation, the reaction solution is poured into methanol for reprecipitation, and then dried to obtain a polyimide (1) 2 having the following structural formula.
9.5 g were obtained.

[0048]

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Reference Example 2 According to the method of Reference Example 1,
1,3-bis (3,4-dicarboxyphenyl) -1,
20.4 g (0.048 mol) of 1,3,3-tetramethyldisiloxane dianhydride, 3,3 ′, 4,4 ′
3.5 g of biphenyltetracarboxylic dianhydride (0.
012 mol) and 200 g of diethylene glycol dimethyl ether as a solvent, to which 2,2-bis [4
-(4-aminophenoxy) phenyl] propane24.
6 g (0.060 mol) of a diethylene glycol dimethyl ether solution (60 g) was added to obtain an imide compound solution.

After cooling the polyimide solution obtained by the above operation, the solution was poured into methanol for reprecipitation, and then dried to obtain 43.2 g of polyimide (2) having the following general structural formula.
I got

[0051]

Embedded image

REFERENCE EXAMPLE 3 17.8 g (0.04 mol) of 2,2-bis (3,4-benzenedicarboxylic acid anhydride) perfluoropropane was placed in a flask equipped with a stirrer, a thermometer and a nitrogen purge device. 200 g of N-methyl-2-pyrrolidone was charged as a solvent, and 80 g of a N-methyl-2-pyrrolidone solution in which 10.0 g (0.05 mol) of diaminodiphenyl ether was dissolved was gradually added dropwise. After completion of the dropwise addition, the mixture was further stirred at room temperature for 10 hours. Then, a reflux condenser with a water receiver was attached to the flask, 30 g of xylene was added, the temperature of the reaction system was raised to 160 ° C., and the temperature was maintained for 6 hours. . By this reaction, 1.3
g of water was produced.

To the yellow-brown reaction solution obtained by the above operation, 5.0 g (0.02 mol) of 3-isocyanatopropyltriethoxysilane was added as a silicon compound.
Stirring was continued at room temperature for 10 hours. After 10 hours, the obtained reaction solution was poured into methanol to give the following compound (A)
1 g was obtained.

[0054] was observed infrared absorption spectrum of the product, the absorption of isocyanate 2300 cm ^-1 is not observed, the absorption derived from the urea bond was observed at 1660 cm ^-1, the curable resin of interest Generation was confirmed.

[0055]

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[Reference Example 4] In the same manner as in Reference Example 3,
22.2 g of 2-bis (3,4-benzenedicarboxylic anhydride) perfluoropropane (0.05 mol)
l), 2.2 g (0.02 mol) of p-aminophenol
1), 8.0 g of diaminodiphenyl ether (0.04
with N-methyl-2-pyrrolidone in 200 g of N-methyl-2-pyrrolidone. Then, 4.9 g (0.02 mol) of 3-isocyanatopropyltriethoxysilane was added to this solution, and a compound (B) having the following general structural formula was added. ) 31.2 g were obtained.

[0057]

Embedded image

Reference Example 5 According to the method of Reference Example 3,
1,3-bis (3,4-dicarboxyphenyl) -1,
13. Using 20.4 g (0.048 mol) of 1,3,3-tetramethyldisiloxane dianhydride and 200 g of diethylene glycol dimethyl ether as a solvent, 2,2-bis [4- (4-aminophenoxy) phenyl] propane was used. 8 g (0.036 mol) and 60 g of a diethylene glycol dimethyl ether solution of 3.3 g (0.024 mol) of m-aminobenzoic acid were added to obtain a solution of an imide compound.

Without isolating the imide compound, 5.2 g (0.0 g) of 3-isocyanatopropylmethyldiethoxysilane was added as a silicon compound to the solution.
24 mol) and 0.05 g of triethylenediamine to obtain 39.6 g of the following compound (C) as an objective.

[0060]

Embedded image

Reference Example 6 According to the method of Reference Example 3,
1,3-bis (3,4-dicarboxyphenyl) -1,
20.4 g (0.048 mol) of 1,3,3-tetramethyldisiloxane dianhydride, 200 g of diethylene glycol dimethyl ether as a solvent, and 2,2-bis [4- (4-aminophenoxy) phenyl] propane were used. 6 g (0.060 mol) of a diethylene glycol dimethyl ether solution (60 g) was added to obtain an imide compound solution.

Without isolating the imide compound, 5.2 g (0.0 g) of 3-isocyanatopropylmethyldiethoxysilane was added as a silicon compound to the solution.
24 mol), and the following curable resin 43.
8 g were obtained.

[0063]

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Reference Example 7 According to the method of Reference Example 3,
14.71 g (0.05 mol) of 3 ', 4,4'-biphenyltetracarboxylic dianhydride and 200 g of N-methyl-2-pyrrolidone as a solvent were charged.
9.9 g (0.04 mol) of bis (3-aminopropyl) 1,1,3,3-tetramethyldisiloxane was added,
Next, 60 g of a solution of 8.2 g (0.02 mol) of 2,2-bis [4- (4-aminophenoxy) phenyl] propane in N-methyl-2-pyrrolidone was added, and 3-isocyanatophenyltrimethoxysilane was further added. 4.8
g (0.02 mol) was added to obtain the desired curable resin shown below.

[0065]

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[Examples] The polyimides (1) and (2) obtained in Reference Examples 1 and 2 and the compounds (A) to (C) obtained in Reference Examples 3 to 5, and diethylene glycol as a solvent Diethyl ether (D), N-methyl-2-
Using pyrrolidone (E), triethylene glycol dimethyl ether (F), and cyclohexanone (G), a resin solution composition having a non-volatile content of 20% was prepared.
The storage stability at 3 ° C. after 3 months was tested by measuring the viscosity using an Ostwald viscometer. Also, S
After coating on an SiO ₂ substrate and leaving it for 3 hours, 150 ° C / 1
hr. + 300 ° C./1 hr. The resin film cured under the conditions described above was evaluated for adhesion to the substrate by a burring test, and the solvent resistance to N-methyl-2-pyrrolidone was immersed in N-methyl-2-pyrrolidone for 1 minute. Tested. Table 1 shows the results.

[0067]

[Table 1]

From the results in Table 1, it can be seen that the resin solution compositions obtained in Examples 1 to 6 have excellent storage stability and have good adhesiveness to a substrate when heated to about 300 ° C. , And that a resin film having excellent solvent resistance was formed.

Claims (3)

(57) [Claims] 1. The following structural formula (1): And Y is selected from an aromatic ring-containing diamine residue having 6 to 30 carbon atoms and a siloxane having 2 to 20 silicon atoms, and a silicon diamine residue having a silethylene and silphenylene skeleton. A divalent group, p is an integer of 1 or more. 100 parts by weight of a polyimide soluble in an organic solvent represented by the following structural formula (2): (However, R ¹ and R ² have the same or different carbon atoms of 1
An unsubstituted or halogen- or alkoxy-substituted monovalent group selected from an alkyl group, an alkenyl group and an aryl group, R ³ having 1 to 9 carbon atoms, an alkylene group, an arylene group,
Z is a monovalent group selected from an oxyalkylene group, an iminoalkylene group, an oxyalkylenearylene group and an iminoalkylene group; and Z is an aromatic ring-containing diamine residue, an aminophenol residue and an aminocarboxylic acid residue having 6 to 30 carbon atoms. A divalent group selected from groups, W is O or NH, and X and Y have the same meaning as described above. k is 0 or 1, m is an integer of 1 to 3, and n is an integer of 1 to 100. A) a curable resin composition containing 1 to 500 parts by weight of a compound represented by the formula: 2. A curable resin composition obtained by dissolving the composition according to claim 1 in an organic solvent. 3. A protective film for an electronic component, comprising a cured product of the composition according to claim 1.