| 摘要 |
PROBLEM TO BE SOLVED: To provide a resin composition which is used suitably as a heat radiating member of an exothermic electronic component such as a power device, particularly as an insulating layer and a thermal interface material of a printed wiring board and is excellent in thermal conductivity and relative dielectric constant and to provide boron nitride powder to be packed in the resin composition.SOLUTION: The boron nitride powder is characterized in that the calcium content thereof is 500-5,000 ppm, the porosity is 50-80%, the average sphericity is 0.7 or higher, the average particle size is 20-100 μm and the peak intensity ratio I(002)/I(100) of the (002) plane to the (100) plane is 9.0 or lower in a powder X-ray diffraction method. The graphitization index of the boron nitride powder is preferably 1.6-4.0 according to the powder X-ray diffraction method. The resin composition contains the boron nitride powder. |
