JPH0892356A - Resin composition - Google Patents

Abstract

PURPOSE: To provide a resin composition having excellent curability, extremely high storage stability at normal temperature and remarkable industrial merits to dispense with the refrigeration storage, refrigeration transportation, etc., when used as a material for electronic or electrical parts. CONSTITUTION: This resin composition contains (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(DBU) and a partial ring-opened product of a carboxylic acid and/or its anhydride having >=4 carboxyl groups in one molecule and forming an ion pair with DBU by giving at least one proton to the DBU and (D) 40-2,400 pts.wt. of an inorganic filler based on 100 pts.wt. of A+B.

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 a "polyvalent carboxylic acid" (C) that forms an ion pair with DBU by giving at least one proton to this DBU is converted into (A) + (B).
The content of the inorganic filler (E) is 0.5 to 20 parts by weight per 100 parts by weight, and the inorganic filler (E) is (A) + (B) 10.
It is a resin composition containing 40 parts by weight or more and 2400 parts by weight or less with respect to 0 parts by weight.

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 "polyvalent carboxylic acid" (C) is a proton having at least one "polyvalent carboxylic acid" (C) which donates a proton to DBU. To form an ion pair, and specific examples of the “polyvalent carboxylic acid” (C) include benzenetetracarboxylic acid, naphthalenetetracarboxylic acid, biphenyltetracarboxylic acid, 2,2-bis (3 , 4-dicarboxydiphenyl) propane, benzophenonetetracarboxylic acid, aromatic tetracarboxylic acids such as bis (3,4-dicarboxydiphenyl) ether and ring-opened products of these anhydrides, ethylenetetracarboxylic acid, methylcyclohexenedicarboxylic acid Ring-opened product of acid anhydride, 4,8-dimethyl-
1,2,3,5,6,7-hexahydronaphthalene-
1,2,5,6-tetracarboxylic acid, cyclopentane-
Aliphatic tetracarboxylic acids such as 1,2,3,4-tetracarboxylic acid, ring-opened products of maleic anhydride copolymers with various olefins such as isobutylene and styrene, and linear polymeric carboxylic acids such as polyacrylic acid Examples thereof include, but are not particularly limited to these examples, pyromellitic acid and polyacrylic acid are particularly preferable in view of the cost of raw materials and availability. Further, all of the ring-opened products and partially ring-opened products of the exemplified carboxylic acid anhydrides and mixtures thereof are also included.

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.

There is no problem to add conventionally known additives to the resin composition of the present invention as needed. Specific examples include release agents, flame retardants such as antimony oxide and halides, pigments such as carbon black, and surface treatment agents of inorganic fillers such as silane coupling agents.

[0012]

The salt (D) of DBU and "polyvalent carboxylic acid" (C) used in the present invention is an ion in which the "polyvalent carboxylic acid" (C) donates at least one proton to DBU. The curing accelerator (D) forms a pair.
At room temperature, the ion pair (salt) of DBU and "polycarboxylic acid" (C) exists stably, which suppresses the catalytic action of DBU and promptly dissociates this ion pair during molding exposed to high temperature. However, DBU is activated and has an action of promoting curing. This curing accelerator (D) is the total weight of the epoxy resin (A) and the phenol resin (B) 10
The content is preferably 0.5 parts by weight or more and 20 parts by weight or less, and less than 0.5 parts by weight causes a decrease in curability. The decrease causes problems such as unfilling failure.

[0013]

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

(Synthesis Example 1) 300 g of acetone and 30.0 g of pyromellitic acid were placed in a 500 ml three-neck separable flask equipped with a cooling tube, and when completely dissolved, DBU was added.
18.0 g was slowly added dropwise. The deposited salt was filtered and vacuum dried at 80 ° C. to obtain a salt of DBU and pyromellitic acid (hereinafter abbreviated as DBU-PMA).

(Synthesis Example 2) In a 300 ml three-neck separable flask equipped with a cooling tube, 80 g of methanol and 15.0 g of polyacrylic acid AC-10P manufactured by Toa Gosei Chemical Industry Co., Ltd.
Then, 31.7 g of DBU was slowly added dropwise. After reacting for 1 hour after completion of dropping, 1
After heating to 00 ° C. and distilling off 45 g of methanol and concentrating the reaction product, it was transferred to a vat and vacuum dried at 100 ° C.
BU and polyacrylic acid salt (abbreviated as DBU-PA below)
Got

(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., 4.0 parts of DBU-PMA obtained in Synthesis Example 1 as a curing accelerator, fused silica 3
00 parts and 2 parts of carnauba wax are mixed, and it is 8 with a hot roll.
The mixture was kneaded at 5 ° C for 5 minutes to obtain a molding material. The spiral flow at 175 ° C. by transfer molding of this molding material was 78 cm, and the Barcol hardness in molding at 175 ° C. for 60 seconds was 85. 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 75 cm, and the flow residual rate (flow after storage for 6 months at 25 ° C./initial flow × 100 (%)) was 96%.

(Example 2) The curing accelerator DBU of Example 1
Example 1 except that 4.0 parts of PMA were used instead of 2.4 parts of DBU-PA obtained in Synthesis Example 2 as the curing accelerator.
It was made into a material by the same operation as. This material had a spiral flow of 73 cm and a Barcol hardness of 84 at 60 seconds.
The spiral flow after storage at 25 ° C for 6 months is 71
In cm, the residual flow rate was 97%.

(Example 3) 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 Dures Co., Ltd.) having a softening point of 95 ° C. and a hydroxyl equivalent of 103,
The same operation as in Example 1 was carried out except that 6.0 parts of DBU-PMA and 2300 parts of fused silica were used as the curing accelerator. The spiral flow of this material is 58c
The Barcol hardness at m, 60 seconds was 60. Also, 2
The spiral flow after storage at 5 ° C for 6 months was 54 cm, and the residual flow rate was 93%.

Comparative Example 1 Phenol novolac of Example 1 was replaced with 33 parts of the curing accelerator DBU-PMA of 4.0 parts, and 31.1 parts of phenol novolac and the curing accelerator of D 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
-A material was produced in the same manner as in Example 1 except that 0.8 part of triphenylphosphine (abbreviated as TPP) was used as a curing accelerator instead of 4.0 part of PMA. 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) The curing accelerator DBU of Example 1
-Instead of 4.0 parts of PMA, DBU-PM 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 3 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.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication C08L 63/00 NKT H01L 23/29 23/31

Claims (5)

[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 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. A partially ring-opened compound (C) of a carboxylic acid having at least four carboxyl groups in one molecule forming an ion pair with and / or an acid anhydride thereof (hereinafter simply referred to as “polycarboxylic acid”).
(Abbreviated) and (A) + (B) 100
0.5 parts by weight or more and 20 parts by weight or less, and 40 parts by weight or more and 2400 parts by weight or less of the inorganic filler (E) per 100 parts by weight of (A) + (B). A resin composition comprising: 2. The resin composition according to claim 1, wherein the “polycarboxylic acid” (C) is a partially ring-opened product of an aromatic carboxylic acid and / or its acid anhydride. 3. The resin composition according to claim 1, wherein the “polycarboxylic acid” (C) is a partially ring-opened product of pyromellitic acid and / or its acid anhydride. 4. The resin composition according to claim 1, wherein the “polycarboxylic acid” (C) is a partially ring-opened product of a linear polymeric carboxylic acid having a degree of polymerization of 4 or more and / or its acid anhydride. 5. The resin composition according to claim 1, wherein the linear polymeric carboxylic acid is polyacrylic acid.