THERMOSETTING RESIN COMPOSITION AND MOLDED BODY THEREOF

Abstract

The present invention addressed the problem of providing a highly reliable thermosetting resin composition which is suitable for use in a sealing material for a semiconductor device and in which warpings and cracks do not occur even when used in a power device, in particular. The problem is solved by a thermosetting resin composition that includes a thermosetting resin and a curing catalyst, wherein the cured product of the thermosetting resin composition has a storage modulus at 25 C. of 1.010.sup.6 Pa to 1.010.sup.10 Pa and an average linear expansion coefficient at 70 to 210 C. of 100 ppm/K or less.

Claims

1. A thermosetting resin composition comprising a thermosetting resin and a curing catalyst, wherein a cured product of said thermosetting resin composition has a storage modulus at 25 C. of 1.010.sup.6 Pa to 1.010.sup.10 Pa and an average linear expansion coefficient at 70 to 210 C. of 100 ppm/K or less.

2. The resin composition according to claim 1, wherein said cured product of said thermosetting resin composition has a ratio (E1/E3) between the storage modulus at 40 C. (E1) and the storage modulus at 175 C. (E3) of 12.5 or less.

3. The resin composition according to claim 1, wherein said thermosetting resin comprises an epoxy resin.

4. The resin composition according to claim 3, wherein said epoxy resin is an epoxy silicone resin.

5. The resin composition according to claim 3, wherein epoxy groups in said epoxy resin comprise an alicyclic epoxy group.

6. The resin composition according to claim 1, comprising a silicone oil.

7. The resin composition according to claim 1, comprising an inorganic filler.

8. The resin composition according to claim 7, comprising said inorganic filler at a ratio of not less than 60% by weight.

9. The resin composition according to claim 7, wherein said inorganic filler has a linear expansion coefficient of 20 ppm/K or less.

10. The resin composition according to claim 7, wherein said inorganic filler is a spherical filler.

11. The resin composition according to claim 7, wherein said inorganic filler is silica.

12. The resin composition according to claim 1, comprising an acid anhydride.

13. A molded article obtained by curing the resin composition according to claim 1.

14. A semiconductor device sealed with the resin composition according to claim 1.

Description

EXAMPLES

[0188] The present invention will now be described in more detail by way of experimental examples thereof (Synthesis Examples, Examples and Comparative Examples); however, the present invention is not restricted to the below-described Examples as long as they do not depart from the gist of the present invention. The values of the various production conditions and evaluation results in the below-described Examples are meant to indicate the upper limit or lower limit values that are preferred in the embodiments of the present invention, and a preferred range thereof may be a range which is defined by a combination of an upper limit or lower limit value and a value shown in the below-described Example or a combination of values shown in Examples.

[0189] First, the materials and reagents used in Examples and Comparative Examples will be described.

[0190] Epoxy silicones EPSi-1 to EPSi-6 were synthesized as described in Synthesis Examples 1 to 6, respectively. In the below-described Synthesis Examples, the weight-average molecular weight (Mw) and the epoxy value were measured as follows.

[0191] Weight-Average Molecular Weight (Mw)

[0192] The weight-average molecular weight (Mw) of a curable composition was measured by gel permeation chromatography under the following conditions and indicated as a value in terms of standard polystyrene. Further, a 1%-by-mass tetrahydrofuran solution of a polysiloxane was prepared and subsequently filtered through a 0.45-m filter, and the resultant was used as a measurement sample solution.

[0193] Apparatus: Waters 2690 (manufactured by Waters Corporation)

[0194] Columns: KF-G, KF-602.5, KF-603 and KF-604 (manufactured by Showa Denko K.K.)

[0195] Eluent: THF, flow rate: 0.7 mL/min, sample concentration: 1%, injection amount: 10 L

[0196] Epoxy Value

[0197] The epoxy value was measured in accordance with JIS K7236:2001. A precisely weighed sample was dissolved in chloroform, and acetic acid and a tetraethylammonium bromide acetic acid solution were subsequently added thereto, after which the resultant was titrated with a 0.1 mol/L perchloric acid-acetic acid standard solution. The end point was determined using a crystal violet indicator.

Synthesis Example 1

[0198] First, 24.0 g of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 72.6 g of a hydroxy-terminated dimethylpolysiloxane (XC96-723, manufactured by Momentive Performance Materials Japan Inc.), 20 g of isopropyl alcohol and 10.7 g of 1 N hydrochloric acid were mixed with stirring at room temperature for 3 hours. Then, 0.67 g of potassium hydroxide, 22.4 g of isopropyl alcohol and 44.9 g of toluene were further added, and the resultant was heated with stirring under refluxing conditions for 4 hours. Subsequently, the resulting reaction solution was neutralized with an aqueous sodium dihydrogen phosphate solution (10% by weight) and washed with water until the washed water became neutral. Thereafter, volatile components were removed under reduced pressure, whereby an epoxy silicone EPSi-1 having a Mw of 2,500 and an epoxy value of 903 g/eq was obtained.

Synthesis Example 2

[0199] An epoxy silicone EPSi-2 having a Mw of 1,800 and an epoxy value of 636 g/eq was obtained by performing the same operations as in Synthesis Example 1, except that 28.8 g of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and 45.1 g of the hydroxy-terminated dimethylpolysiloxane were mixed with 14.1 g of trimethylethoxysilane, 24 g of isopropyl alcohol and 12.9 g of 1 N hydrochloric acid; and that the amounts of potassium hydroxide, isopropyl alcohol and toluene that were further added were changed to 0.81 g, 26.9 g and 53.9 g, respectively.

Synthesis Example 3

[0200] An epoxy silicone EPSi-3 having a Mw of 8,100 and an epoxy value of 1,200 g/eq was obtained by performing the same operations as in Synthesis Example 1, except that the amounts of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, hydroxy-terminated dimethylpolysiloxane, isopropyl alcohol and 1 N hydrochloric acid were changed to 16.4 g, 70.0 g, 216.0 g and 8.6 g, respectively; and that the amounts of potassium hydroxide, isopropyl alcohol and toluene that were further added were also changed to 0.54 g, 18.0 g and 35.9 g, respectively.

Synthesis Example 4

[0201] An epoxy silicone EPSi-4 having a Mw of 1,000 and an epoxy value of 282 g/eq was obtained by performing the same operations as in Synthesis Example 1, except that 64.8 g of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 40.1 g of trimethylethoxysilane, 45 g of isopropyl alcohol and 24.39 g of 1 N hydrochloric acid were mixed with stirring at room temperature; and that the reagents added thereafter were changed to 1.51 g of potassium hydroxide and 148 g of isopropyl alcohol.

Synthesis Example 5

[0202] An epoxy silicone EPSi-5 having a Mw of 2,700 and an epoxy value of 904 g/eq was obtained by performing the same operations as in Synthesis Example 2, except that the amounts of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, hydroxy-terminated dimethylpolysiloxane, trimethylethoxysilane, isopropyl alcohol, 1 N hydrochloric acid, potassium hydroxide, isopropyl alcohol and toluene were changed to 19.5 g, 55.4 g, 5.2 g, 17.6 g, 9.5 g, 0.59 g, 19.8 g and 39.5 g, respectively.

Synthesis Example 6

[0203] First, 13.00 g of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3.67 g of trimethylethoxysilane, 55.4 g of dimethylsiloxane terminated with silanol at both ends (XC96-723, manufactured by Momentive Performance Materials Inc.), 34.59 g of isopropyl alcohol, 34.59 g of toluene and 6.99 g of 1 N potassium hydroxide were mixed with stirring at room temperature for 2 hours. The resultant was further heated with stirring at 73 C.2 C. under refluxing conditions for 6 hours. Then, the resulting reaction solution was neutralized with an aqueous sodium dihydrogen phosphate solution (10% by weight) and washed with water until the washed water became neutral. Thereafter, volatile components were removed under reduced pressure, whereby an epoxy silicone EPSi-6 having a Mw of 3,300 and an epoxy value of 1,160 was obtained.

[0204] Other reagents are as follows.

[0205] Silicone oil 1 is a methylphenylpolysiloxane which has a refractive index of 1.523 and a weight-average molecular weight of about 1,600 in terms of polystyrene and contains a silanol group at both ends. The structure thereof is represented by the following Formula (33).

##STR00011##

[0206] Silicone oil 2 is a polymethylphenylsiloxane having a weight-average molecular weight of about 900 in terms of polystyrene. Specifically, the silicone oil 2 is FLD516 manufactured by Bluestar Silicones International, which has a structure represented by the following Formula (34). In the Formula (34), the average of n is 5 to 10.

##STR00012##

[0207] YED-216D (manufactured by Mitsubishi Chemical Corporation) is an alkyldiglycidyl ether having a structure represented by the following Formula (35).

##STR00013##

[0208] YL7410 (manufactured by Mitsubishi Chemical Corporation) is an epoxy resin having a polyether chain as a structural unit.

[0209] 1,3-bis[2-(3,4-epoxycyclohexane-1-yl)ethyl]-1,1,3,3-tetramethylpropane disiloxane is manufactured by Gelest Inc. and has a structure represented by the following Formula (36).

##STR00014##

[0210] SANSOCIZER E-PO is manufactured by New Japan Chemical Co., Ltd. (chemical name: diepoxystearyl epoxyhexahydrophthalate) and has a structure represented by the following Formula (37). In the Formula (37), R represents a 9,10-epoxystearyl group.

##STR00015##

[0211] jER871 (manufactured by Mitsubishi Chemical Corporation) is a flexible epoxy resin.

[0212] RIKACID MH-700 is a liquid alicyclic acid anhydride manufactured by New Japan Chemical Co., Ltd., in which 4-methylhexahydrophthalic anhydride represented by the Formula (38) and hexahydrophthalic anhydride represented by the Formula (39) are mixed at a ratio of 7/3. RIKACID MH-700 is used as a curing agent for epoxy resins.

##STR00016##

[0213] MEH-8000H is a liquid phenol novolac manufactured by Meiwa Plastic Industries, Ltd. and used as a liquid curing agent for epoxy resins.

[0214] Ga(acac).sub.3 (gallium acetylacetonate) is a complex formed by a Ga.sup.3+ cation and acetylacetone and has a structure represented by the following Formula (40).

##STR00017##

<Measurement of Physical Properties of Cured Products>

[0215] The physical properties of the cured products obtained in the below-described Examples and Comparative Examples were measured as follows.

[0216] Measurement of Average Linear Expansion Coefficient

[0217] A plate-form cured product of 1 to 2 mm in thickness was cut out in a size of 3 mm3 mm and used as a measurement sample.

[0218] The linear expansion coefficient was measured in accordance with JIS K7197 using EXSTAR TMA/SS6100 (manufactured by SII NanoTechnology Inc.) as a thermomechanical analyzer in the compression mode following the temperature programs shown in Table 1, and the average linear expansion coefficient was determined in the program 3.

TABLE-US-00001 TABLE 1 Temperature program C. C. C./min 1 40 220 5 2 220 80 50 3 80 220 5 4 220 40 50

[0219] Measurement of Storage Modulus (E)

[0220] A plate-form cured product of 1 to 2 mm in thickness was cut out into a strip of 15 mm in length and 5 mm in width and used as a measurement sample.

[0221] The storage modulus was measured in accordance with JIS K7244 using EXSTAR DMS/SS6100 (manufactured by SII NanoTechnology Inc.) as a thermomechanical analyzer in the tensile mode at a frequency of 1 Hz following the temperature programs shown in Table 2, and the storage modulus at 25 C. was determined in the program 1.

TABLE-US-00002 TABLE 2 Temperature program C. C. C./min 1 70 200 4 2 200 30 50

Example 1

[0222] First, 3.00 g of EPSi-1, 1.00 g of silicone oil 1, 0.40 g of YED216D and 35.28 g of a true spherical filler HL-3100 (manufactured by Tatsumori Ltd.) were added and mixed with stirring.

[0223] To the resulting liquid, 0.273 g of an acid anhydride-based curing agent MH700 and 0.138 g of a Ga(acac).sub.3 solution obtained by dissolving 2% by weight of gallium acetylacetonate in the silicone oil 2 were added, and the resultant was mixed with stirring to obtain a thermosetting resin composition (hereinafter, abbreviated as curable composition) (LME-1).

[0224] The thus obtained curable composition (LME-1) was coated to a thickness of 1 cm on KO-PWR110682 (Ni-plated copper-clad silicon nitride substrate) manufactured by KYOCERA Corporation and heat-cured in an oven under the curing conditions shown in Table 3 below: at 80 C. for 30 minutes, at 120 C. for 60 minutes and at 150 C. for 180 minutes, whereby a 1 cm-thick cured product (HLME-1) was obtained on the substrate.

[0225] Further, in order to measure the average linear expansion coefficient and storage modulus of the cured product (HLME-1), 4.0 to 6.0 g of the curable composition (LME-1) was placed on a 5-mm aluminum dish and heat-cured in an oven under the curing conditions shown in Table 3 below: at 80 C. for 30 minutes, at 120 C. for 60 minutes and at 150 C. for 180 minutes, whereby a plate-form cured product having a thickness of about 1 to 2 mm (HLME-1) was obtained.

[0226] After the heat-curing, the outer appearance (occurrence of cracking) of the 1 cm-thick cured product (HLME-1) on the substrate was observed. The occurrence of cracking and peeling of the thus obtained cured product was visually verified. In addition, for the plate-form cured product (HLME-1) detached from the aluminum dish, the average linear expansion coefficient in a temperature range of 70 to 210 C. and the storage modulus (E2) at 25 C. were measured by the above-described physical property measurement methods. The storage modulus was also measured at 40 C. and 175 C., and the thus obtained values were defined as E1 and E3, respectively.

Examples 2 to 12 and Comparative Examples 1 and 2

[0227] Curable compositions (LME-2) to (LME-14) were obtained in the same manner as the curable composition (LME-1) by mixing the respective components with stirring at the weight ratios shown in Table 3 below.

[0228] The thus obtained curable compositions (LME-2) to (LME-14) were, in the same manner as the curable composition (LME-1), each coated to a thickness of 1 cm on a KO-PWR110682 substrate manufactured by KYOCERA Corporation and heat-cured in an oven under the curing conditions shown in Table 3 below. As a result, 1 cm-thick cured products (HLME-2) to (HLME-9) and (HLME-12) to (HLME-14) and comparative cured products (HLME-10) and (HLME-11) were each obtained on the substrate.

[0229] Further, in order to measure the average linear expansion coefficient and storage modulus of the cured products (HLME-2) to (HLME-14), the curable compositions (LME-2) to (LME-14) were each placed on a 5-mm aluminum dish in an amount of 4.0 to 6.0 g and heat-cured in an oven under the above-described conditions, whereby plate-form cured products (HLME-2) to (HLME-14) each having a thickness of about 1 to 2 mm were obtained.

[0230] After the heat-curing, the outer appearance was observed for the 1 cm-thick cured products (HLME-2) to (HLME-14) on the substrate. The presence or absence of cracking and peeling in each cured product was visually verified. In addition, for each of the plate-form cured products (HLME-2) to (HLME-14) detached from the aluminum dish, the average linear expansion coefficient in a temperature range of 70 to 210 C. and the storage modulus (E2) at 25 C. were measured in the same manner as in the case of the cured product (HLME-1). The storage modulus was also measured at 40 C. and 175 C., and the thus obtained values were defined as E1 and E3, respectively.

[0231] For the above-described Examples 1 to 12 and Comparative Examples 1 and 2, Table 3 shows the amount (g) of each component contained in the respective curable compositions, the epoxy value (g/eq) of each epoxy compound, the curing conditions, and the results of measuring the physical properties of each cured product.

TABLE-US-00003 TABLE 3-1 Example/Comparative Example Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Name of resin composition LME-1 LME-2 LME-3 LME-4 LME-5 LME-6 LME-7 Epoxy silicone EPSi-1 (g) 3 2 3 0 4.2 0 0 resin EPSi-2 (g) 0 0 0 3 0 2 0 EPSi-3 (g) 0 0 0 0 0 0 4 EPSi-4 (g) 0 0 0 0 0 0 0 EPSi-5 (g) 0 0 0 0 0 0 0 Silicone oil Silicone oil 1 (g) 1 2 0 1 0 0 0 Silicone oil 2 (g) 0 0 1 0 0 0 0 Organic epoxy YED216D (g) 0.4 0.4 0 0 0.4 0.4 0 compound YL-7410 0 0 0 0 0 0 0 1,3-bis[2-(3,4- 0 0 0 0.47 0 0 0 epoxycyclohexane-1- yl)ethyl]-1,1,3,3- tetramethylpropane disiloxane (g) SANSOCIZER E-PO (g) 0 0 0 0 2 2 0 j ER871 (g) 0 0 0 0 0 0 0 Filler HL-3100 (g) 35.28 34.94 31.097 35.56 52.9 44.3 38.47 Curing agent MH700 (g) 0.273 0.227 0.1025 0 0.36 0.384 0.137 Lauric anhydride 0 0 0 0 0 0 0 MEH-8000H (g) 0 0 0 0.243 0 0 0 Curing catalyst Ga(acac).sub.3/FLD solution (g) 0.138 0.138 0.138 0.131 0.138 0.138 0.138 Name of cured product HLME-1 HLME-2 HLME-3 HLME-4 HLME-5 HLME-6 HLME-7 Curing conditions 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 120 C., 1 h 120 C., 1 h 120 C., 1 h 120 C., 2 h 120 C., 1 h 120 C., 1 h 120 C., 1 h 150 C., 3 h 150 C., 3 h 150 C., 3 h 150 C., 1 h 150 C., 3 h 150 C., 3 h 150 C., 3 h 200 C., 1 h Linear expansion coefficient (ppm/K) 26 19 46 43 30 18 47 Storage modulus E1 @ 40 C. 3.3E+09 9.2E+08 5.1E+08 5.8E+09 3.7E+09 4.6E+09 9.9E+08 (Pa) E2 @ 25 C. 1.4E+09 3.0E+08 2.5E+08 1.6E+09 4.2E+08 1.3E+08 5.7E+08 E3 @ 175 C. 2.5E+08 6.4E+07 1.2E+08 2.6E+08 8.5E+07 2.8E+07 1.6E+08 E1/E3 13.2 14.4 4.3 22.3 43.5 164.3 6.2 Occurrence of without KYOCERA cracking substrate wall at the time of curing Example/Comparative Example Comparative Comparative Example 8 Example 9 Example 10 Example 11 Example 12 Example 1 Example 2 Name of resin composition LME-8 LME-9 LME-12 LME-13 LME-14 LME-10 LME-11 Epoxy silicone EPSi-1 (g) 1.08 1 0 0 1.08 0 0 resin EPSi-2 (g) 0 0 0 0 0 4 0 EPSi-3 (g) 0 0 0 0 0 0 0 EPSi-4 (g) 0 0 0 0 0 0 4 EPSi-5 (g) 0 0 1.08 1 0 0 0 Silicone oil Silicone oil 1 (g) 0 0 0 0 0 0 0 Silicone oil 2 (g) 0 0 0 0 0 0 0 Organic epoxy YED216D (g) 0.216 0.216 0.216 0.216 0 0.474 0.474 compound YL-7410 0.81 1 0 0 0 0 0 1,3-bis[2-(3,4- 0 0 0 0 0 0 0 epoxycyclohexane-1- yl)ethyl]-1,1,3,3- tetramethylpropane disiloxane (g) SANSOCIZER E-PO (g) 1.08 1 1.08 1 0.216 0 0 j ER871 (g) 0 0 0.81 1 0.81 0 0 Filler HL-3100 (g) 32.29 32.64 32.32 32.69 0 6.4 38.9 Curing agent MH700 (g) 0.263 0.273 0.267 0.278 1.08 0.416 0.737 Lauric anhydride 0 0 0 0 32.29 0 0 MEH-8000H (g) 0 0 0 0 0.263 0 0 Curing catalyst Ga(acac)3/FLD solution (g) 0.138 0.138 0.138 0.138 0 0.132 0.132 Name of cured product HLME-8 HLME-9 HLME-12 HLME-13 HLME-14 HLME-10 HLME-11 Curing conditions 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 120 C., 2 h 120 C., 2 h 120 C., 1 h 120 C., 1 h 120 C., 1 h 120 C., 2 h 120 C., 2 h 150 C., 1 h 150 C., 1 h 150 C., 3 h 150 C., 3 h 150 C., 1 h 150 C., 1 h 150 C., 1 h 200 C., 1 h 200 C., 1 h 180 C., 3 h 200 C., 1 h 200 C., 1 h Linear expansion coefficient (ppm/K) 29 21 34 26 19 137 20 Storage E1 @ 40 C. 3.6E+09 4.1E+09 3.1E+09 3.3E+09 3.7E+09 2.3E+09 1.3E+10 modulus (Pa) E2 @ 25 C. 8.0E+08 1.1E+09 7.6E+08 6.9E+08 2.3E+09 7.4E+08 1.1E+10 E3 @ 175 C. 1.3E+08 1.3E+08 1.0E+08 1.1E+08 2.8E+08 1.1E+08 4.8E+09 E1/E3 27.7 31.5 31.0 30.0 13.2 20.9 2.7 Occurrence of without KYOCERA substrate x x cracking wall at the time of curing

[0232] As clearly seen from the results shown in Table 3, the cured products (HLME-1) to (HLME-9) and (HLME-12) to (HLME-14), which were obtained in Examples 1 to 12, satisfied both the condition of having a storage modulus at 25 C. of 1.010.sup.6 Pa to 1.010.sup.10 Pa and the condition of having an average linear expansion coefficient at 70 to 210 C. of 100 ppm/K or less, and cracking was not observed on the 1 cm-thick cured products on the substrate (occurrence of cracking: ). On the other hand, the cured products (HLME-10) and (HLME-11) of Comparative Examples 1 and 2 did not satisfy either the condition of having a storage modulus at 25 C. of 1.010.sup.6 Pa to 1.010.sup.10 Pa or the condition of having an average linear expansion coefficient at 70 to 210 C. of 100 ppm/K or less, and cracking from the substrate was observed (occurrence of cracking: x).

[0233] The details of the mechanism that caused cracking in the cured products of Comparative Examples 1 and 2 are not clear; however, it is believed that, for example, since the average linear expansion coefficient of the cured product was not sufficiently reduced in Comparative Example 1 due to the excessively small amount of the inorganic filler and the epoxy value of the epoxy silicone resin was too small (excessively high epoxy density) in Comparative Example 2, these cured products had a high elastic modulus and a large internal stress was thus generated by the temperature change during the curing, as a result of which cracking occurred.

Examples 13 to 16

[0234] Curable compositions (LME-15) to (LME-18) were obtained in the same manner as the curable composition (LME-1) by mixing the respective components with stirring at the weight ratios shown in Table 4 below.

[0235] In Table 4, DPhSiOH (chemical name: diphenylsilane diol) is manufactured by Tokyo Chemical Industry Co., Ltd., and its chemical structure is represented by the following Formula (41).

##STR00018##

[0236] The octanoic anhydride and nonanoic anhydride are manufactured by Tokyo Chemical Industry Co., Ltd., and their chemical structures are represented by the following Formulae (42) and (43), respectively.

##STR00019##

[0237] X-22-169B is a modified silicone manufactured by Shin-Etsu Chemical Co., Ltd., and has the following structure.

##STR00020##

[0238] The thus obtained curable compositions (LME-15) to (LME-18) were, in the same manner as the curable composition (LME-1), each coated to a thickness of 1 cm on a KO-PWR110682 substrate manufactured by KYOCERA Corporation and heat-cured in an oven under the curing conditions shown in Table 4 below, whereby cured products (HLME-15) to (HLME-18) were obtained. For the thus obtained cured products, the presence or absence of cracking and peeling was visually verified.

[0239] Further, after fixing a stainless-steel frame around a copper-clad silicon nitride substrate (KO-PWR131845, manufactured by KYOCERA Corporation) with a Kapton tape, the curable compositions (LME-15) to (LME-18) were each poured onto the substrate in an amount of about 17 to 19 g and subsequently cured under the curing conditions shown in Table 4 below, whereby cured products (HLME-15) to (HLME-18) were obtained on the framed substrate. The thus obtained cured products were cooled to room temperature over a period of about 1 hour and then subjected to a heat cycle test. The heat cycle test was performed using a thermal shock apparatus TSA-41L-A manufactured by ESPEC Corp. and, after performing 140 cycles each consisting of 30-minute exposure to a high temperature of 175 C., 1-minute exposure to normal temperature and 30-minute exposure to a low temperature of 40 C., each sample was taken out and the presence or absence of cracking and peeling in the cured product was visually verified.

[0240] Further, in order to measure the average linear expansion coefficient and storage modulus of the cured products (HLME-15) to (HLME-18), the curable compositions (LME-15) to (LME-18) were each placed on a 5-mm aluminum dish in an amount of 4.0 to 6.0 g and heat-cured in an oven under the above-described conditions, whereby plate-form cured products (HLME-15) to (HLME-18) each having a thickness of about 1 to 2 mm were obtained. For each of the plate-form cured products detached from the aluminum dish, the average linear expansion coefficient in a temperature range of 70 to 210 C. and the storage modulus (E2) at 25 C. were measured in the same manner as in the case of the cured product (HLME-1). The storage modulus was also measured at 40 C. and 175 C., and the thus obtained values were defined as E1 and E3, respectively.

[0241] For the above-described Examples 13 to 16 and Comparative Examples 1 and 2, Table 4 shows the amount (g) of each component contained in the respective curable compositions, the epoxy value (g/eq) of each epoxy compound, the curing conditions, and the results of measuring the physical properties of each cured product.

TABLE-US-00004 TABLE 4 Example/Comparative Example Comparative Comparative Example 13 Example 14 Example 15 Example 16 Example 1 Example 2 Name of resin composition LME-15 LME-16 LME-17 LME-18 LME-10 LME-11 Epoxy silicone resin EPSi-2 (g) 0 0 0 0 4 0 EPSi-4 (g) 0 0 0 0 0 4 EPSi-6 (g) 0 0 0.1 0 0 0 X-22-169B (g) 1 1 0.9 1 0 0 Organic epoxy compound YED216D (g) 0 0 0 0 0.474 0.474 Filler HL-3100 (g) 6.02 5.91 10.26 10.3 6.4 38.9 Curing agent MH700 (g) 0 0 0 0 0.416 0.737 Octanoic anhydride 0.04 0.02 0.037 0 0 0 Nonanoic anhydride 0 0 0 0.0439 MEH-8000H (g) 0 0.01 0 0 0 0 Curing catalyst Ga(acac).sub.3 solution (g) 0 0 0.103 0.103 0.132 0.132 Ga(acac).sub.3 0.002 0.002 0 0 0 0 DPhSiOH 0.02 0.01 0 0 0 0 Name of cured product HLME-15 HLME-16 HLME-17 HLME-18 HLME-10 HLME-11 Curing conditions 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 120 C., 1 h 120 C., 1 h 120 C., 1 h 120 C., 1 h 120 C., 2 h 120 C., 2 h 150 C., 1 h 150 C., 1 h 150 C., 1 h 150 C., 1 h 150 C., 1 h 150 C., 1 h 180 C., 3 h 180 C., 3 h 180 C., 3 h 180 C., 3 h 200 C., 1 h 200 C., 1 h Linear expansion coefficient (ppm/K) 84 71 62 47 137 20 Storage modulus (Pa) E1 @ 40 C. 9.8E+06 1.3E+07 6.9E+07 4.9E+07 2.3E+09 1.3E+10 E2 @ 25 C. 6.6E+06 8.9E+06 2.8E+07 2.2E+07 7.4E+08 1.1E+10 E3 @ 175 C. 5.7E+06 8.5E+06 1.0E+07 1.6E+07 1.1E+08 4.8E+09 E1/E3 1.7 1.5 6.9 3.1 20.9 2.7 Occurrence of cracking at the time of curing x x after 140 heat cycles x x

[0242] As clearly seen from the results shown in Table 4, the cured products (HLME-15) to (HLME-18) obtained in Examples 13 to 16 satisfied both the condition of having a storage modulus at 25 C. of 1.010.sup.6 Pa to 1.010.sup.10 Pa and the condition of having an average linear expansion coefficient at 70 to 210 C. of 100 ppm/K or less, and cracking was not observed on the 1 cm-thick cured products on the substrate (occurrence of cracking: ). On the other hand, the cured products (HLME-10) and (HLME-11) of Comparative Examples 1 and 2 did not satisfy either the condition of having a storage modulus at 25 C. of 1.010.sup.6 Pa to 1.010.sup.10 Pa or the condition of having an average linear expansion coefficient at 70 to 210 C. of 100 ppm/K or less, and cracking from the substrate was observed (occurrence of cracking: x).

[0243] In addition, the cured products (HLME-15) to (HLME-18) obtained in Examples 13 to 16 satisfied the condition of having a ratio (E1/E3) between the storage modulus at 40 C. and the storage modulus at 175 C. of 12.5 or less, and the cured products on the framed substrate were not observed with cracking (occurrence of cracking: ). On the other hand, the cured products (HLME-10) and (HLME-11) did not satisfy any one of the condition of having a storage modulus at 25 C. of 1.010.sup.6 Pa to 1.010.sup.10 Pa, the condition of having an average linear expansion coefficient at 70 to 210 C. of 100 ppm/K or less and the condition of having a ratio (E1/E3) between the storage modulus at 40 C. and the storage modulus at 175 C. of 12.5 or less, and the cured products on the framed substrate were observed with cracking (occurrence of cracking: x).

[0244] In the cured products (HLME-15) to (HLME-18), it is believed that excellent inhibition of cracking was attained since stress could be sufficiently alleviated due to the low storage modulus and a low elasticity was stably maintained over a wide temperature range due to the small ratio (E1/E3) between the storage modulus at 40 C. and the storage modulus at 175 C.

Example 17

[0245] First, 0.40 g of DENACOL EX-216L, 1.0 g of SANSOCIZER E-PO, 1.40 g of jER871 and 29.3 g of a true spherical filler HL-3100 (manufactured by Tatsumori Ltd.) were added and mixed with stirring.

[0246] It is noted here that DENACOL EX-216L is manufactured by Nagase ChemteX Corporation (chemical name: cyclohexane dimethanol diglycidyl ether) and has a structure represented by the following Formula (44).

##STR00021##

[0247] To the resulting liquid, 0.314 g of an acid anhydride-based curing agent MH700 and 0.138 g of a Ga(acac).sub.3 solution obtained by dissolving 2% by weight of gallium acetylacetonate in a silicone oil were added, and the resultant was mixed with stirring to obtain a thermosetting resin composition (hereinafter, abbreviated as curable composition) (LME-19).

[0248] The thus obtained curable composition (LME-19) was coated to a thickness of 1 cm on KO-PWR110682 (Ni-plated copper-clad silicon nitride substrate) manufactured by KYOCERA Corporation and heat-cured in an oven under the curing conditions shown in Table 5 below: at 80 C. for 30 minutes, at 120 C. for 60 minutes, at 150 C. for 60 minutes and at 180 C. for 180 minutes, whereby a 1 cm-thick cured product (HLME-19) was obtained on the substrate.

[0249] Further, in order to measure the average linear expansion coefficient and storage modulus of the cured product (HLME-19), 4.0 to 6.0 g of the curable composition (LME-19) was placed on a 5-mm aluminum dish and heat-cured in an oven under the curing conditions shown in Table 5 below: at 80 C. for 30 minutes, at 120 C. for 60 minutes, at 150 C. for 60 minutes and at 180 C. for 180 minutes, whereby a plate-form cured product having a thickness of about 1 to 2 mm (HLME-19) was obtained.

[0250] After the heat-curing, the outer appearance (occurrence of cracking) of the 1 cm-thick cured product (HLME-19) on the substrate was observed. In addition, for the plate-form cured product (HLME-19) detached from the aluminum dish, the average linear expansion coefficient in a temperature range of 70 to 210 C. and the storage modulus at 25 C. were measured by the above-described physical property measurement methods.

[0251] Further, after fixing a stainless-steel frame around a copper-clad silicon nitride substrate (KO-PWR131845, manufactured by KYOCERA Corporation) with a Kapton tape, the curable composition (LME-19) was poured onto the substrate in an amount of about 17 to 19 g and subsequently cured under the curing conditions shown in Table 5 below, whereby a cured product (HLME-19) was obtained on the framed substrate. The thus obtained cured product was cooled to room temperature over a period of about 1 hour and then subjected to a heat cycle test. The heat cycle test was performed using a thermal shock apparatus TSA-41L-A manufactured by ESPEC Corp. and, after performing 140 cycles each consisting of 30-minute exposure to a high temperature of 175 C., 1-minute exposure to normal temperature and 30-minute exposure to a low temperature of 40 C., the sample was taken out and the presence or absence of cracking and peeling in the cured product was visually verified.

[0252] For the above-described Example 17 and Comparative Examples 1 and 2, Table 5 shows the amount (g) of each component contained in the respective curable compositions, the curing conditions, and the results of measuring the physical properties of each cured product.

TABLE-US-00005 TABLE 5 Example/Comparative Example Comparative Comparative Example 17 Example 1 Example 2 Name of resin composition LME-19 LME-10 LME-11 Epoxy silicone resin EPSi-2 (g) 0 4 0 EPSi-4 (g) 0 0 4 Organic epoxy EX-216 (g) 0.4 0 0 compound SANSOCIZER E-PO (g) 1 0 0 jER871 (g) 1.4 0 0 YED216D (g) 0 0.474 0.474 Filler HL-3100 (g) 29.30 6.4 38.9 Curing agent MH700 (g) 0.314 0.416 0.737 Curing catalyst Ga(acac).sub.3 solution (g) 0.103 0.132 0.132 Name of cured product HLME-19 HLME-10 HLME-11 Curing conditions 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 120 C., 1 h 120 C., 2 h 120 C., 2 h 150 C., 1 h 150 C., 1 h 150 C., 1 h 180 C., 3 h 200 C., 1 h 200 C., 1 h Linear expansion coefficient (ppm/K) 30 137 20 Storage modulus (Pa) E2 @ 25 C. 3.4E + 07 7.4E + 08 1.1E + 10 Occurrence of cracking x x

[0253] As clearly seen from the results shown in Table 5, the cured product (HLME-19) obtained in Example 17 satisfied both the condition of having a storage modulus at 25 C. of 1.010.sup.6 Pa to 1.010.sup.10 Pa and the condition of having an average linear expansion coefficient at 70 to 210 C. of 100 ppm/K or less, and cracking was not observed on the 1 cm-thick cured product on the substrate (occurrence of cracking: ). On the other hand, the cured products (HLME-10) and (HLME-11) of Comparative Examples 1 and 2 did not satisfy either the condition of having a storage modulus at 25 C. of 1.010.sup.6 Pa to 1.010.sup.10 Pa or the condition of having an average linear expansion coefficient at 70 to 210 C. of 100 ppm/K or less, and cracking from the substrate was observed (occurrence of cracking: x).

Examples 18 to 26

[0254] Curable compositions (LME-20) to (LME-28) were obtained by mixing the respective components with stirring at the weight ratios shown in Table 6 below. Specifically, after adding a true spherical filler HL-3100 to X-22-169B and mixing the resultant with stirring, a solution obtained by dissolving gallium acetylacetonate and DPhSiOH in octanoic anhydride or lauric anhydride, or a silicone oil 3, 4 or 5, was added to the resulting liquid, and the resultant was mixed with stirring.

[0255] The silicone oil 3 is a methylphenylpolysiloxane having a silanol group at both ends, whose refractive index is 1.475 and weight-average molecular weight is about 1,900 in terms of polystyrene.

[0256] The silicone oil 4 is a carbinol-modified silicone oil having an epoxy value of 950 and a viscosity at 25 C. of 45 mm.sup.2/s.

[0257] The silicone oil 5 is a carbinol-modified silicone oil having an epoxy value of 1,600 and a viscosity at 25 C. of 140 mm.sup.2/s.

TABLE-US-00006 TABLE 6 Example/Comparative Example Example 18 Example 19 Example 20 Example 21 Example 22 Name of resin composition LME-20 LME-21 LME-22 LME-23 LME-24 Epoxy silicone resin X-22-169B (g) 1 1 1 1 1 Silicone oil Silicone oil 3 (g) 0.0509 0.0509 0 0 0.06 Silicone oil 4 (g) 0 0 0.2 0 0 Silicone oil 5 (g) 0 0 0 0.2 0 Filler HL-3100 (g) 9.88 9.87 7.18 7.18 6.30 Curing agent MH700 (g) 0 0 0 0 0 Octanoic anhydride 0.0398 0.0398 0.0398 0.0398 0.0398 Lauric anhydride 0 0 0 0 0 Curing catalyst Ga(acac).sub.3 0.00216 0.0011 0.0025 0.0025 0.0022 DPhSiOH 0.0053 0.0053 0.024 0.024 0.0107 Name of cured product HLME-20 HLME-21 HLME-22 HLME-23 HLME-24 Curing conditions 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 120 C., 1 h 120 C., 1 h 120 C., 1 h 120 C., 1 h 120 C., 1 h 150 C., 1 h 150 C., 1 h 150 C., 1 h 150 C., 1 h 150 C., 1 h 180 C., 3 h 180 C., 3 h 180 C., 3 h 180 C., 3 h 180 C., 3 h Linear expansion coefficient (ppm/K) 37 31 66 81 76 Storage modulus (Pa) E1 @ 40 C. 5.3E+07 6.2E+07 1.1E+07 8.9E+06 3.0E+07 E2 @ 25 C. 2.0E+07 2.5E+07 6.1E+06 5.4E+06 1.3E+07 E3 @ 175 C. 9.8E+06 8.4E+06 4.1E+06 4.2E+06 7.0E+06 E1/E3 5.4 7.4 2.7 2.1 4.3 Occurrence of cracking at the time of curing after 140 heat cycles Example/Comparative Example Example 23 Example 24 Example 25 Example 26 Name of resin composition LME-25 LME-26 LME-27 LME-28 Epoxy silicone resin X-22-169B (g) 1 1 1 1 Silicone oil Silicone oil 3 (g) 0.0509 0.126 0 0 Silicone oil 4 (g) 0 0 0 0 Silicone oil 5 (g) 0 0 0 0 Filler HL-3100 (g) 6.22 6.68 5.96 6.11 Curing agent MH700 (g) 0 0 0 0 Octanoic anhydride 0.0398 0.0398 0.0398 0 Lauric anhydride 0 0 0 0.0563 Curing catalyst Ga(acac).sub.3 0.0022 0.0023 0.0021 0.0021 DPhSiOH 0.0053 0.0113 0.0101 0.0205 Name of cured product HLME-25 HLME-26 HLME-27 HLME-28 Curing conditions 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 80 C., 0.5 h 120 C., 1 h 120 C., 1 h 120 C., 1 h 120 C., 1 h 150 C., 1 h 150 C., 1 h 150 C., 1 h 150 C., 1 h 180 C., 3 h 180 C., 3 h 180 C., 3 h 180 C., 3 h Linear expansion coefficient (ppm/K) 56 75 68 91 Storage modulus (Pa) E1 @ 40 C. 1.6E+07 3.0E+07 6.2E+06 1.5E+07 E2 @ 25 C. 7.1E+06 1.5E+07 4.3E+06 8.6E+06 E3 @ 175 C. 3.8E+06 1.0E+07 4.0E+06 6.3E+06 E1/E3 4.2 3.0 1.6 2.4 Occurrence of cracking at the time of curing after 140 heat cycles

REFERENCE EXAMPLES

Reference Example 1

[0258] Using a planetary mixer (Planetary Vacuum Mixer ARV-300, manufactured by THINKY Corporation), 2.3 parts by weight of the EPSi-6, 3.3 parts by weight of jER871 (manufactured by Mitsubishi Chemical Corporation), 0.9 parts by weight of DENACOL EX-216L (cyclohexane dimethanol diglycidyl ether, manufactured by Nagase ChemteX Corporation), 2.3 parts by weight of SANSOCIZER E-PO (diepoxystearyl epoxyhexahydrophthalate, manufactured by New Japan Chemical Co., Ltd.) and 90.0 parts by weight of a true spherical filler HL-3100 (manufactured by Tatsumori Ltd.) were mixed with stirring.

[0259] Then, to the resulting mixture, 0.8 parts by weight of an acid anhydride-based curing agent MH700 (manufactured by New Japan Chemical Co., Ltd.) and 0.3 parts by weight of a liquid (Ga(acac).sub.3 solution) obtained by dissolving 2% by weight of gallium acetylacetonate (manufactured by Strem Chemicals, Inc.) in FLD516 (polymethylphenylsiloxane terminated with a hydroxy group at both ends, manufactured by Bluestar Silicones International: weight-average molecular weight in terms of polystyrene=about 900) were added, and the resultant was mixed with stirring to obtain a composition 1.

<Tensile Test of Epoxy Compound>

[0260] The epoxy compound of interest in an amount of 1 g, an acid anhydride-based curing agent MH700 (manufactured by New Japan Chemical Co., Ltd.) at a ratio of 1:1 with respect to the epoxy equivalent of the epoxy compound and HISHICOLIN PX-4MP (manufactured by Nippon Chemical Industrial Co., Ltd.) weighed in an amount of 0.01 g were stirred using a stirrer.

[0261] The thus obtained mixture was coated on an aluminum dish having an inner diameter of 7 mm at a thickness of about 1 mm and cured in an oven by sequential heating at 100 C. for 1.5 hours and then at 140 C. for 1.5 hours. The resulting cured product was cut out in a size of 30 mm4 mm, and measurement was performed in accordance with JIS K7162 using STA-1225 manufactured by ORIENTEC Co., Ltd. as a tensile tester under the following conditions.

[0262] Full-scale load: 500 N

[0263] Initial sample length: 20 mm

[0264] Testing rate: 20 mm/min

[0265] Environmental humidity: 60% RH; Temperature: 25 C.

[0266] The measurement was performed three times (n=3), and an average value was calculated for the elongation at break and the breaking strength.

<Evaluation of Composition Viscosity>

[0267] The thus obtained composition (about 6 g) was placed in a 6-cc ointment container, and the viscosity was measured at 40 to 20 C. using a vibration-type viscometer manufactured by Sekonic Corporation (model: VM-10A-H). A value obtained by dividing the viscometer-indicated value at 25 C. by the specific gravity was taken as the measurement value.

<Bending Test of Cured Product>

[0268] The composition 1 was coated to a thickness of 2 mm using a self-made mold and cured in an oven by sequential heating under the following conditions: at 80 C. for 30 minutes, at 120 C. for 60 minutes, at 150 C. for 60 minutes and then at 180 C. for 180 minutes. After cutting out the thus obtained cured product into a size of 50 mm5 mm, measurement was performed in accordance with JIS K7171 (PlasticsDetermination of flexural properties) using RSA-III manufactured by TA Instruments Inc. with a measurement tool (3-pt bending tool) under the following conditions.

[0269] Geometry: Three-point bending geometry

[0270] Test setup: MultiExtension

[0271] Test parameter: Temperature=25[ C.]

[0272] Extension Rate: 0.01 [mm/s]

[0273] Delay before test: 5 [s]

[0274] The measurement was performed three times (n=3), and an average value of the bending strain at break was calculated.

[0275] <Production of Cured Product and Observation of Cracking>

[0276] After fixing a stainless-steel plate around a copper-clad silicon nitride substrate (KO-PWR131845, manufactured by KYOCERA Corporation) with a Kapton tape, the composition 1 was poured onto the substrate in an amount of about 34 to 38 g and subsequently cured by sequential heating under the following conditions: at 80 C. for 30 minutes, at 120 C. for 60 minutes, at 150 C. for 60 minutes and then at 180 C. for 180 minutes, whereby a cured product 1 was obtained. After cooling the thus obtained cured product to room temperature over a period of about 1 hour, the stainless-steel plate was removed, and the presence or absence of cracking and peeling on the upper and side surfaces of the cured product was visually verified.

[0277] The results thereof are shown in Table 7.

TABLE-US-00007 TABLE 7 Tensile Reference Elongation (%) strength (MPa) Example 1 Composition Epoxy EPSi-6 19 0.29 2.3 compound E-PO 32 0.1 2.3 jER871 44 1.3 3.3 EX-216L 7.5 50 0.9 YED-216L 4.5 38.5 0 YL-7410 18.6 0.43 0 Filler HL-3100 90 Curing agent MH700 0.8 Catalyst Ga(2%)-FLD 0.3 Physical Slurry viscosity (Pa .Math. s) 19 properties of composition Physical Bending strain (%) @ 25 C. 6.2 properties of cured product Cracking at the time of curing No Crack

[0278] In Reference Example 1, no cracking was observed. In Reference Example 1, it is believed that, by incorporating an epoxy compound showing a large elongation and a high breaking strength in the tensile test, a sealing resin composition showing a large bending strain in the bending test, in which stress is suppressed and cracking is unlikely to occur, was obtained.

Reference Example 2

<Synthesis of Epoxy Silicone Resin>

[0279] First, 64.8 g of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 40.1 g of trimethylethoxysilane, 45 g of isopropyl alcohol and 24.39 g of 1 N hydrochloric acid were mixed with stirring at room temperature for 3 hours. Then, 1.51 g of potassium hydroxide and 148 g of isopropyl alcohol were further added, and the resultant was heated with stirring under isopropyl alcohol refluxing conditions for 4 hours. Subsequently, the resulting reaction solution was neutralized with an aqueous sodium dihydrogen phosphate solution (10% by weight) and washed with water until the washed water became neutral. Thereafter, volatile components were removed under reduced pressure, whereby a polysiloxane EPSi-7 having a Mw of 4,002 was obtained.

[0280] Using a planetary vacuum mixer ARV-300 manufactured by THINKY Corporation, 0.5 g of the EPSi-7, 0.5 g of E-PO (manufactured by New Japan Chemical Co., Ltd.), 0.25 g of jER871 (manufactured by Mitsubishi Chemical Corporation), 0.36 g of YED216D (manufactured by Mitsubishi Chemical Corporation) and 16.9 g of a true spherical filler HL-3100 (manufactured by Tatsumori Ltd.) were mixed with stirring. Then, to the resulting mixture, 0.20 g of an acid anhydride-based curing agent RIKACID MH700 (manufactured by New Japan Chemical Co., Ltd.) and 0.069 g of a liquid (Ga(acac).sub.3 solution) obtained by dissolving 2% by weight of gallium acetylacetonate (manufactured by Strem Chemicals, Inc.) in FLD516 (polymethylphenylsiloxane terminated with a hydroxy group at both ends, manufactured by Bluestar Silicones International: weight-average molecular weight in terms of polystyrene=about 900) were added, and the resultant was further mixed with stirring to obtain a composition.

[0281] The hydrogen bond term in the Hansen parameters of the matrix resin of the thus obtained composition was determined as follows. In this composition, E-PO, jER871, YED216D and MH-700 correspond to the matrix resin. The amounts of these components in % by weight are 38.2, 19.1, 27.4 and 15.3, respectively. Further, these components have a specific gravity of 0.985, 0.985, 1.03 and 1.15, respectively, and a hydrogen bond term in the Hansen parameters of 3.9, 4, 6.9 and 6, respectively. Based on these values, the products of the hydrogen bond term in the Hansen parameters of the respective components and the volume fraction of the respective components are calculated to be 1.51, 0.78, 1.83 and 0.80, respectively, and the sum of these values is 4.92. This value was taken as the hydrogen bond term of the Hansen parameters for the matrix resin.

Reference Examples 3 to 8

[0282] Each resin composition was obtained by mixing the components shown in Table 8 in accordance with the method of Reference Example 2.

Reference Comparative Examples 1 to 3

[0283] Each resin composition was obtained by mixing the components shown in Table 8 in accordance with the method of Reference Example 2.

<Evaluation of Composition Fluidity>

[0284] In the present embodiment, the fluidity is defined as follows. A resin composition is said to have fluidity if the resin composition cannot maintain its form for 30 minutes or longer when 2 g thereof is weighed in a hand-holdable aluminum cup No. 2 (manufactured by AS ONE Corporation) and tilted by 90 on a 40 C. hot plate.

TABLE-US-00008 TABLE 8 Components Weight- average molecular Reference Example Composition Component name weight H 2 3 4 5 6 Silicone EPSi-7 4,002 2.66 2.7 2.66 1.13 2.75 Matrix resin E-PO (manufactured by New Japan Chemical Co., Ltd.) 691 3.9 2.66 2.7 2.66 2.27 2.75 JER871 (manufactured by Mitsubishi Chemical 1,576 4 1.33 1.33 1.33 4.08 1.37 Corporation) YL7410 (manufactured by Mitsubishi Chemical 1,560 8.1 Corporation) YED216D (manufactured by Mitsubishi Chemical 230 6.9 1.91 Corporation) EX216L (manufactured by Nagase ChemteX Corporation) 256 6.9 1.91 0.91 EX146 (manufactured by Nagase ChemteX Corporation) 206 4.7 1.91 1.97 Diglycidyl 1,2-cyclohexanedicarboxylate (manufactured by 284 8.2 Tokyo Chemical Industry Co., Ltd.) EX850L (manufactured by Nagase ChemteX Corporation) 218 8.5 EX313 (manufactured by Nagase ChemteX Corporation) 260 9.4 MH700 (manufactured by New Japan Chemical Co., Ltd.) 690 6 1.06 1.06 1.06 0.84 0.78 Silanol source FLD516 (manufactured by Bluestar Silicones 878 0.37 0.37 0.38 0.31 0.38 compound International) Metal catalyst Ga(acac).sub.3 (manufactured by Strem Chemicals, Inc.) 0.0074 0.0074 0.0076 0.0062 0.0076 Filler HL-3100 (manufactured by Tatsumori Ltd.) 90 90 90 90 90 Hydrogen bond term in Hansen parameters of matrix resin 4.92 4.92 4.34 4.45 Fluidity Components Weight- average Reference Reference Comparative molecular Example Example Composition Component name weight H 7 8 1 2 3 Silicone EPSi-7 4,002 2.09 1.27 2.66 2.66 2.66 Matrix resin E-PO (manufactured by New Japan Chemical Co., Ltd.) 691 3.9 3.13 2.54 2.66 2.66 2.66 JER871 (manufactured by Mitsubishi Chemical 1,576 4 2.08 3.56 1.33 1.33 1.33 Corporation) YL7410 (manufactured by Mitsubishi Chemical 1,560 8.1 1.25 Corporation) YED216D (manufactured by Mitsubishi Chemical 230 6.9 0.42 1.18 Corporation) EX216L (manufactured by Nagase ChemteX Corporation) 256 6.9 EX146 (manufactured by Nagase ChemteX Corporation) 206 4.7 Diglycidyl 1,2-cyclohexanedicarboxylate (manufactured by 284 8.2 1.91 Tokyo Chemical Industry Co., Ltd.) EX850L (manufactured by Nagase ChemteX Corporation) 218 8.5 1.91 EX313 (manufactured by Nagase ChemteX Corporation) 260 9.4 1.91 MH700 (manufactured by New Japan Chemical Co., Ltd.) 690 6 0.73 1.15 1.06 1.06 0.97 Silanol source FLD516 (manufactured by Bluestar Silicones 878 0.29 0.37 0.37 0.37 0.37 compound International) Metal catalyst Ga(acac).sub.3 (manufactured by Strem Chemicals, Inc.) 0.0058 0.0074 0.0074 0.0074 0.0074 Filler HL-3100 (manufactured by Tatsumori Ltd.) 90 90 90 90 90 Hydrogen bond term in Hansen parameters of matrix resin 5.27 5.35 5.59 Fluidity x x x The numerical values of components represent the amount (% by weight) of each component in the composition.

[0285] As clearly seen from the results shown in Table 8, the resin compositions of Reference Examples 2 to 8 had fluidity. On the other hand, the resin compositions of Reference Comparative Examples 1 to 3 did not have fluidity.

Reference Example 9

<Synthesis of Epoxy Silicone Resin>

[0286] First, 16.30 g of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 5.22 g of trimethylethoxysilane, 69.27 g of dimethylsiloxane terminated with silanol at both ends (XC96-723, manufactured by Momentive Performance Materials Inc.), 17.57 g of isopropyl alcohol and 9.48 g of 1 N hydrochloric acid were mixed with stirring at room temperature for 3 hours. Then, 0.60 g of potassium hydroxide, 19.91 g of isopropyl alcohol and 39.75 g of toluene were further added, and the resultant was heated with stirring under isopropyl alcohol refluxing conditions for 4 hours. Subsequently, the resulting reaction solution was neutralized with an aqueous sodium dihydrogen phosphate solution (10% by weight) and washed with water until the washed water became neutral. Thereafter, volatile components were removed under reduced pressure, whereby a polysiloxane EPSi-8 having a Mw of 1,000 was obtained.

[0287] Using a planetary mixer (Planetary Vacuum Mixer ARV-300, manufactured by THINKY Corporation), 1.12 g of a liquid (including BL-S: 0.12 g and E-PO: 1.0 g), which was prepared in advance by dissolving 1.0 g of the EPSi-8, 1.4 g of an epoxy resin jER871 (manufactured by Mitsubishi Chemical Corporation), 0.4 g of cyclohexane dimethanol diglycidyl ether (DENACOL EX-216L, manufactured by Nagase ChemteX Corporation) and 0.24 g of a polyvinyl butyral resin (S-LEC B BL-S, manufactured by Sekisui Chemical Co., Ltd.) in 2.0 g of diepoxystearyl epoxyhexahydrophthalate (SANSOCIZER E-PO, manufactured by New Japan Chemical Co., Ltd.), and 39.65 g of a true spherical filler HL-3100 (manufactured by Tatsumori Ltd.) were mixed with stirring.

[0288] Then, to the resulting mixture, 0.348 g of an acid anhydride-based curing agent MH700 (manufactured by New Japan Chemical Co., Ltd.) and 0.138 g of a liquid (Ga(acac).sub.3 solution) obtained by dissolving 2% by weight of gallium acetylacetonate (manufactured by Strem Chemicals, Inc.) in FLD516 (polymethylphenylsiloxane terminated with a hydroxy group at both ends, manufactured by Bluestar Silicones International: weight-average molecular weight in terms of polystyrene=about 900) were added, and the resultant was further mixed with stirring to obtain a resin composition 1.

Reference Example 10

[0289] A resin composition 2 was obtained in the same manner as in Reference Example 9 by mixing the respective components with stirring at the weight ratios shown in Table 9 below.

Reference Example 11

[0290] Using a planetary mixer (Planetary Vacuum Mixer ARV-300, manufactured by THINKY Corporation), 1.0 g of the EPSi-8, 1.4 g of an epoxy resin jER871 (manufactured by Mitsubishi Chemical Corporation), 0.4 g of cyclohexane dimethanol diglycidyl ether (DENACOL EX-216L, manufactured by Nagase ChemteX Corporation), 1.0 g of diepoxystearyl epoxyhexahydrophthalate (SANSOCIZER E-PO, manufactured by New Japan Chemical Co., Ltd.), 0.2 g of Nylon 12 particles (SP-500, manufactured by Toray Industries, Inc.; average particle size=5 m, spherical) and 39.65 g of a true spherical filler HL-3100 (manufactured by Tatsumori Ltd.) were mixed with stirring.

[0291] Then, to the resulting mixture, 0.348 g of an acid anhydride-based curing agent MH700 (manufactured by New Japan Chemical Co., Ltd.) and 0.138 g of a liquid (Ga(acac).sub.3 solution) obtained by dissolving 2% by weight of gallium acetylacetonate (manufactured by Strem Chemicals, Inc.) in FLD516 (polymethylphenylsiloxane terminated with a hydroxy group at both ends, manufactured by Bluestar Silicones International: weightaverage molecular weight in terms of polystyrene=about 900) were added, and the resultant was further mixed with stirring to obtain a resin composition 3.

Reference Comparative Example 4

[0292] A resin composition 4 was obtained in the same manner as in Reference Example 9, except that no polyvinyl butyral resin was added.

<Evaluation of Composition Viscosity>

[0293] The thus obtained compositions (about 6 g) were each placed in a 6-cc ointment container, and the viscosity was measured at 40 to 20 C. using a vibration-type viscometer manufactured by Sekonic Corporation (model: VM-10A-H). Values obtained by dividing the viscometer-indicated value at 25 C. by the specific gravity were taken as the measurement values and shown in Table 9.

<Evaluation of Storage Modulus of Cured Products>

[0294] The resin compositions 1 to 4 were each placed in an aluminum dish having an inner diameter of 5 mm in an amount of 6 g and cured in an oven by sequential heating under the following conditions: at 80 C. for 30 minutes, at 120 C. for 60 minutes, at 150 C. for 60 minutes and then at 180 C. for 180 minutes. For the thus obtained cured products, the storage modulus was measured in accordance with JIS K7244 using EXSTAR DMS/6100 manufactured by SII NanoTechnology Inc. as a thermomechanical analyzer in the tensile mode at a frequency of 1 Hz by heating each cured product from 70 C. to 200 C. at a rate of 4 C./min. The results of the storage modulus at 25 C. are shown in Table 9.

<Measurement of Linear Expansion Coefficient of Cured Products>

[0295] The resin compositions 1 to 4 were each placed in an aluminum dish having an inner diameter of 5 mm in an amount of 6 g and cured in an oven by sequential heating under the following conditions: at 80 C. for 30 minutes, at 120 C. for 60 minutes, at 150 C. for 60 minutes and then at 180 C. for 180 minutes. For the thus obtained cured products, the linear expansion coefficient was measured in accordance with JIS K7197 using TMA/SS6100 manufactured by SII NanoTechnology Inc. as a thermomechanical analyzer in the compression mode, and the average linear expansion coefficient was determined in a temperature range of 70 C. to 210 C. The data obtained in the step 3 of the following heating/cooling program were used. The results are shown in Table 9.

(Analysis Conditions)

[0296] Sample shape: 3 mm3 mm, thickness=1 mm to 3 mm

[0297] SS program: 49.01 mN, constant

[0298] Step 1: 40 to 220 C., 5-min retention, 5 C./min

[0299] Step 2: 220 to 80 C., 5-min retention, 50 C./min

[0300] Step 3: 80 to 220 C., 5-min retention, 5 C./min

<Heat Shock Test Results>

[0301] A frame was prepared around a nickel-plated copper-clad silicon nitride substrate (KO-PWR110682, manufactured by KYOCERA Corporation), and the resin compositions 1 to 4 were each poured onto the substrate in an amount of about 34 to 38 g and subsequently cured by sequential heating under the following conditions: at 80 C. for 30 minutes, at 120 C. for 60 minutes, at 150 C. for 60 minutes and then at 180 C. for 180 minutes. Thereafter, the surrounding frame was removed to obtain a sealed substrate sample. This sample was subjected to a heat shock test. The heat shock test was performed using a thermal shock apparatus TSA-41L-A manufactured by ESPEC Corp., and the sample was taken out every 70 cycles, each consisting of 30-minute exposure to a high temperature of 175 C., 1-minute exposure to normal temperature and 30-minute exposure to a low temperature of 40 C., and the presence or absence of cracking and peeling in the composition was visually verified.

[0302] The results thereof are shown in Table 9.

TABLE-US-00009 TABLE 9 Reference Comparative Reference Example Example 9 10 11 4 Formulation of liquid resin Thermosetting resin EPSi-8 1 1 1 1 composition E-PO 1 1 1 1 jER871 1.4 1.8 1.4 1.4 EX-216L 0.4 0.4 0.4 0.4 Thermoplastic resin S-LEC B BL-S 0.12 0.12 0 0 SP-500 0 0 0.2 0 Silica filler HL-3100 39.654 43.612 40.374 38.57 Curing agent MH700 0.348 0.387 0.348 0.346 Curing catalyst Ga(2%)-FLD 0.138 0.138 0.138 0.138 Physical property of Slurry viscosity (Pa .Math. s) 18 18 17 10 composition Composition 1 Composition 2 Composition 3 Composition 4 Physical properties of Storage modulus, E (Pa) at 25 C. 3.70E+08 5.90E+08 1.70E+08 8.30E+08 cured product CTE (ppm/K) 28 8.4 9.3 18.7 70 C. to 210 C. Heat shock results 280 420 350 280 x

[0303] The resin composition 4 containing no thermoplastic resin was cracked after 280 heat shock cycles; however, in the resin compositions 1 to 3 containing a thermoplastic resin, no cracking was observed after 280, 350 and 420 cycles, respectively. Based on these results, it is believed that the sealing resin compositions unlikely to be cracked were obtained because stress was alleviated in the resin compositions 1 to 3 by the incorporation of a thermoplastic resin.

[0304] While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.