JPH07188395A - Resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition having excellent curability and extremely excellent storage stability at normal temperature and exhibiting remarkable industrial merits e.g. to dispense with the refrigeration storage and the refrigerating transportation when used as a material for electronic and electric parts. CONSTITUTION:This resin composition is composed of (A) an epoxy resin having >=2 epoxy groups in one molecule, (B) a phenolic resin having >=2 phenolic hydroxyl groups in one molecule (the equivalent ratio of the epoxy group to the phenolic hydroxyl group is 0.5-2), (C) 0.5-20 pts.wt. (based on 100 pts.wt. of A+B) of a cure accelerator consisting of a salt of 1,8-diazabicyclo[5,4,0]-7- undecene (abbreviated to DBU) and an organic compound forming an ion pair with the DBU by giving at least one proton to the DBU and (D) 40-2,400 pts.wt. (based on 100 pts.wt. of A+B) of an inorganic filler.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition for electronic and electric parts which is excellent in curability and has good storage stability at room temperature.

[0002]

2. Description of the Related Art In recent years, epoxy resin compositions have been generally used as a sealing material for semiconductor elements such as ICs and LSIs and electric parts, from the viewpoint of characteristics and cost balance.

In such an epoxy resin sealing material,
Conventionally used curing accelerators include 2-methylimidazole, DBU, triphenylphosphine, and the like, but epoxy resin encapsulants using these curing accelerators have poor storage stability at room temperature, and therefore, room temperature. When stored at 1, there was a problem that unfilled defects occurred during molding due to deterioration of flowability, and gold wires of IC chips were broken, leading to defective conduction.

For this reason, at present, it is necessary to store the epoxy resin encapsulating material in a refrigerating state, and it is a current situation that a great deal of cost is required for refrigerating storing and refrigerating transportation.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a resin composition for electronic and electric parts, which has excellent curability and storage stability at room temperature.

[0006]

The present invention provides an epoxy resin (A) having two or more epoxy groups in one molecule and a phenol resin (B) having two or more phenolic hydroxyl groups in one molecule. The equivalent ratio of the group to the phenolic hydroxyl group is 0.5 or more and 2 or less, and further, as a curing accelerator, 1,8-diazabicyclo [5,4,0] -7-
A salt (D) consisting of undecene (DBU) and an organic compound (C) which forms an ion pair with DBU by giving at least one proton to this DBU is added to 0 parts by weight of (A) + (B). A resin composition containing 0.5 parts by weight or more and 20 parts by weight or less and further containing 40 parts by weight or more and 2400 parts by weight or less of the inorganic filler (E) with respect to 100 parts by weight of (A) + (B). is there.

Specific examples of the epoxy resin (A) include orthocresol novolac epoxy, phenol novolac epoxy, bisphenol A type epoxy,
Examples thereof include biphenyl type epoxy, but are not limited thereto. Further phenol resin (A)
Examples thereof include phenol novolac and cresol novolac. In these (A) and (B), the equivalent ratio of the epoxy group to the phenolic hydroxyl group is 0.5.
It is preferably 2 or more, and outside this range, problems such as lower glass transition temperature and lower curability occur.

The salt (D) of DBU which is a curing accelerator and the organic compound (C) forms an ion pair when the organic compound (C) which donates a proton to DBU gives at least one proton. As a specific example of the organic compound (C), acetic acid, trifluoroacetic acid, benzoic acid, and those having a functional group in the aromatic nucleus of benzoic acid, phthalic acid, trimellitic acid, polyacrylic acid, and other various compounds Examples thereof include molecularized carboxylic acids, isocyanuric acid, and 1,2,3-benzotriazole. Among them, carboxylic acids and isocyanuric acid are particularly preferable.

Further, the amount of the curing accelerator (D) added is 1 total weight of the epoxy resin (A) and the phenol resin (B).
It is preferably 0.5 parts by weight or more and 20 parts by weight or less with respect to 00 parts by weight. If the amount is less than 0.5 parts by weight, the curability will be deteriorated, and if the amount is more than 20 parts by weight, the curing will be too fast and problems such as unfilling failure will occur during molding.

Examples of the inorganic filler used in the present invention include alumina, fused silica, crystalline silica, clay and talc, but the inorganic filler is not particularly limited thereto. The amount of the inorganic filler (E) added is the resin component (A),
40 parts by weight or more based on 100 parts by weight of (B) 2
It is preferably 400 parts by weight or less, and when it is less than 40 parts by weight, it causes a problem such as a decrease in strength when it is used as a molding material, and when it is more than 2400 parts by weight, fluidity deteriorates and a problem such as unfilling failure during molding occurs Occurs.

[0011]

[Function] DBU and organic compound (C) used in the present invention
The salt (D) with and the organic compound (C) donates at least one proton to DBU to form an ion pair, and the curing accelerator (D) is D at room temperature.
The ion pair (salt) of BU and the organic compound (C) is stably present, which suppresses the catalytic action of DBU and promptly dissociates during molding when exposed to high temperature.
Is activated and has an action of promoting curing.
The curing accelerator (D) is preferably 0.5 parts by weight or more and 20 parts by weight or less, and less than 0.5 parts by weight with respect to 100 parts by weight of the total weight of the epoxy resin (A) and the phenol resin (B). If the amount is more than 20 parts by weight, the curing will be too fast and the fluidity will decrease during molding, resulting in problems such as unfilling failure.

[0012]

EXAMPLES The present invention will be described in more detail below with reference to examples.

(Synthesis Example 1) N, N-dimethylformamide (DMF) 6 was added to a 200 ml round bottom flask equipped with a cooling tube.
0 g and 3.27 g of terephthalic acid were added, and when completely dissolved, 3.0 g of DBU was slowly added dropwise. White crystals started to form during the dropping. After the addition of DBU was completed, the reaction was allowed to proceed for 1 hour.
Vacuum dried in DBU and terephthalic acid salt (hereinafter DB
U-TPA) was obtained.

(Synthesis Example 2) 150 g of tetrahydrofuran and 3,5-tetrahydrofuran were placed in a three-neck separable flask equipped with a cooling tube.
15.0 g of dinitrobenzoic acid was added, and when completely dissolved, 10.8 g of DBU was slowly added dropwise. The precipitated salt was filtered and dried in vacuum at 80 ° C.
A salt of dinitrobenzoic acid (hereinafter abbreviated as DBU-DNBA) was obtained.

(Synthesis Example 3) 120 g of DMF and 5.16 g of isocyanuric acid were placed in a three-necked round bottom flask equipped with a cooling tube and heated to 90 ° C. to completely dissolve isocyanuric acid. After that, 6.08 g of DBU was slowly dropped,
Stir for 1 hour after the completion of dropping, then continue stirring,
It was gradually cooled to room temperature to precipitate a salt. The precipitated salt was filtered, washed with toluene, and vacuum dried at 80 ° C. to obtain DBU.
And a salt of isocyanuric acid (hereinafter abbreviated as DBU-ICA) were obtained.

(Example 1) 67 parts of orthocresol novolac epoxy (EOCN-1025-65 manufactured by Nippon Kayaku Co., Ltd.) having a softening point of 65 ° C. and an epoxy equivalent of 210 (hereinafter, all parts by weight are abbreviated), and softened. 33 parts of phenol novolac (PR-51470 manufactured by Sumitomo Durez Co., Ltd.) having a hydroxyl equivalent of 104 at 105 ° C., 1.7 parts of DBU-TPA obtained in Synthesis Example 1 as a curing accelerator, fused silica 3
00 parts and 2 parts of carnauba wax are mixed, and 9 with a hot roll
The mixture was kneaded at 0 ° C. for 5 minutes to obtain a molding material. The spiral flow at 175 ° C. by transfer molding of this molding material was 75 cm, and the Barcol hardness in molding at 175 ° C. for 60 seconds was 82. The spiral flow is a fluidity parameter, and the larger the value, the better the fluidity. The Barcol hardness is a curability parameter, and the larger the value, the better the curability.

Next, the spiral flow of this material after storage at 25 ° C. for 6 months was measured. As a result, the spiral flow was 71 cm, and the flow residual rate (flow after storage for 6 months at 25 ° C./initial flow × 100 (%)) was 95%.

(Example 2) The curing accelerator DBU of Example 1
-A material was prepared in the same manner as in Example 1 except that 2.5 parts of DBU-DNBA obtained in Synthesis Example 2 was used as the curing accelerator instead of 1.7 parts of TPA. This material had a spiral flow of 80 cm and a Barcol hardness of 84 at 60 seconds. The spiral flow after storage at 25 ° C for 6 months was 77 cm, and the residual flow rate was 96%.

Example 3 Curing accelerator DBU of Example 1
In the same manner as in Example 1 except that 2 parts of DBU-ICA obtained in Synthesis Example 3 was used as the curing accelerator instead of 1.7 parts of -TPA, the material was made into a material. This material had a spiral flow of 69 cm and a Barcol hardness of 81 for 60 seconds. In addition, the spiral flow after storage at 25 ° C for 6 months is 67 cm.
The flow residual rate was 97%.

(Example 4) 67 parts of YX-4000H manufactured by Yuka Shell Epoxy Co., Ltd., which is a biphenyl type epoxy,
33 parts of phenol novolac (PR-51714 manufactured by Sumitomo Durez Co., Ltd.) having a softening point of 95 ° C. and a hydroxyl equivalent of 103,
DBU-TPA obtained in Synthesis Example 1 as a curing accelerator.
Example 1 except that 4 parts and 2300 parts of fused silica are used.
It was made into a material by the same operation as. This material had a spiral flow of 55 cm and a Barcol hardness of 62 at 60 seconds.
The spiral flow after storage at 25 ° C for 6 months is 51
In cm, the residual flow rate was 93%.

(Comparative Example 1) In place of 33 parts of the phenol novolac of Example 1 and 1.7 parts of the curing accelerator DBU-TPA, 31.1 parts of phenol novolac and D of the curing accelerator were used.
A material was prepared in the same manner as in Example 1 except that 2.7 parts of BU30% phenol novolac (SA841 manufactured by San-Apro Co., Ltd.) was used. This material had a spiral flow of 73 cm and a Barcol hardness of 70 for 60 seconds. The spiral flow after storage at 25 ° C for 6 months was 49 cm, and the residual flow rate was 67%.

Comparative Example 2 Curing accelerator DBU of Example 1
In the same manner as in Example 1 except that 0.8 part of triphenylphosphine (abbreviated as TPP) was used as a curing accelerator in place of 1.7 parts of TPA, a material was prepared. This material has a spiral flow of 78 cm and a Barcol hardness of 60 seconds of 7
It was 3. The spiral flow after storage at 25 ° C for 6 months was 55 cm, and the residual flow rate was 71%.

(Comparative Example 3) 67 parts of orthocresol novolak epoxy of Example 1 and 33 of phenol novolac
Orthocresol novolak epoxy 30
Parts and 70 parts of phenol novolac were used, and the same procedure as in Example 1 was carried out. An attempt was made to measure the spiral flow of this material, but it could not be measured due to poor curing.

Comparative Example 4 Curing accelerator DBU of Example 1
-In place of 1.7 parts of TPA, DBU-TP was used as a curing accelerator.
All were made into a material by the same operation as in Example 1 except that 30 parts of A was used, but the curing was too fast and molding was impossible.

(Comparative Example 5) Fused silica 300 of Example 1
The material was made into a material by the same operation as in Example 1 except that 2500 parts of fused silica was used instead of parts, but it had almost no fluidity and could not be molded.

The results of Examples 1 to 4 and Comparative Examples 1 to 5 are summarized in Table 1.

[0026]

[Table 1]

[0027]

The resin composition according to the present invention has excellent curability and very good storage stability at room temperature. When the resin composition according to the present invention is used as a material for electronic and electric parts,
There are great advantages for the industry, such as refrigeration storage and refrigeration transportation are unnecessary.

Claims (3)

[Claims] 1. In an epoxy resin (A) having two or more epoxy groups in one molecule and a phenol resin (B) having two or more phenolic hydroxyl groups in one molecule, the equivalent ratio of epoxy groups to phenolic hydroxyl groups. Is 0.5 or more and 2 or less, and further 1,8-diazabicyclo [5,4,0] -7-undecene (hereinafter abbreviated as DBU) as a curing accelerator and at least one proton is given to this DBU. And a salt (D) consisting of an organic compound (C) forming an ion pair with 100 parts by weight of (A) + (B),
The content of the inorganic filler (E) is 0.5 parts by weight or more and 20 parts by weight or less and 40 parts by weight based on 100 parts by weight of (A) + (B).
A resin composition containing at least 2400 parts by weight. 2. The resin composition according to claim 1, wherein the organic compound (C) according to claim 1 is a carboxylic acid having at least one carboxyl group in one molecule. 3. The resin composition according to claim 1, wherein the organic compound (C) according to claim 1 is isocyanuric acid.