TECHNOLOGY FOCUS - POLYMERS - Preferred Composition: The resin composition further contains 0.01-30 parts mass of surface modification agent having radical reactivity with respect to 100 parts mass of inorganic filler. The ethylene-olefin-polyene copolymer has initial-stage tensile elastic modulus of 10 MPa or less, and is obtained by polymerizing ethylene, olefin and hydrocarbon-type polyene using co-catalyst and single-site coordination-polymerization catalyst comprising transition metal compound of formula (I) or (II).A,B'=benzoindenyl, indenyl, cyclopentadienyl or fluorenyl (all optionally substituted) in which 1 or more of substitutable H is substituted by 1-20C alkyl, 6-10C aryl, 7-20C alkylaryl, halo, OSi(R)3, Si(R)3 or P(R)2;R=1-10C hydrocarbyl;Y'=H or methylene group or boron residue (both having 1-15C hydrocarbyl optionally substituted by 1-3 nitrogen, oxygen, sulfur, phosphorus or silicon atom), and optionally has cyclic structure;X=H, hydroxy, halo, 1-20C hydrocarbyl, 1-20C alkoxy, silyl substituted by 1-4C hydrocarbyl, or amide substituted by 1-20C hydrocarbyl, where two X optionally couples;M,M'=zirconium, hafnium or titanium;Cp=cyclopenta phenanthryl, benzoindenyl, cyclopentadienyl, indenyl or fluorenyl (all optionally substituted);Y"=H or methylene, silylene, ethylene, germylene or boron residue (all having 1-15C hydrocarbyl), and optionally has cyclic structure;Z=nitrogen, oxygen or sulfur, or H or group having 1-15C substituent, and is bonded with Y" by ligand coordinated to M' with nitrogen, oxygen or sulfur;X'=H, halo, 1-5C alkyl, 6-10C aryl, 8-12C alkylaryl, silyl having 1-4C hydrocarbyl substituent, 1-10C alkoxy, or dialkylamide having 1-6C alkyl substituent;andn=1 or 2.Preferred Properties: The hardened component has heat conductivity of 1.5-20 W/m.K, storage elastic modulus of 1x 106 Pa or more at 300 degrees C based on viscoelasticity measurement, tensile rupture elongation of 3% or more at 25 degrees C and initial-stage tensile elasticity modulus of 500 MPa or less. The hardened sheet with thickness of 0.5 mm has water vapor-permeation rate of 1 g/m2.24 hours or less.