METHOD FOR PRODUCING BULK BORON NITRIDE POWDER AND HEAT RADIATION MEMBER USING THE SAME

• Main Authors: KUROKAWA FUMIHIRO, NAKAJIMA MICHIHARU, TAKEDA GO, TANIGUCHI YOSHITAKA
• Format: Patent
• Language: English; Japanese
• Published: 16.05.2019
• Subjects: CHEMISTRY; COMPOUNDS THEREOF; INORGANIC CHEMISTRY; METALLURGY; NON-METALLIC ELEMENTS

To provide a boron nitride powder excellent in heat conductivity and fillability.SOLUTION: A method for producing a bulky boron nitride powder is provided which comprises: a step of preparing a bulky boron nitride fine powder that is bulky as a result of the agglomeration of primary particles of flaky hexagonal boron nitride and that has a particle strength of 5.0 MPa or more as determined at the time of cumulative fracture rate of 63.2%, an average particle diameter of 2 μm or more and less than 20 μm, and an orientation index of 20 or less as determined in X-ray diffractometry; a step of preparing a bulky boron nitride fine powder that has a particle strength of 5.0 MPa or more as determined at the time of cumulative fracture rate of 63.2%, an average particle diameter of 20 μm or more and 100 μm or less, and an orientation index of 10 or less as determined in X-ray diffractometry; and a step of mixing the boron nitride fine powder with the bulky boron nitride crude powder such that the content ratio of the bulky boron nitride fine powder is in the range from 7 mass% to 50 mass% to give the bulky boron nitride powder.SELECTED DRAWING: None 【課題】熱伝導率および充填性に優れた窒化ホウ素粉末を提供する。【解決手段】累積破壊率６３．２％時の粒子強度が５．０ＭＰａ以上、平均粒径が２μｍ以上２０μｍ未満、Ｘ線回折から求められる配向性指数の値が２０以下の特徴を有する、一次粒子が鱗片状の六方晶窒化ホウ素が凝集して塊状になった塊状窒化ホウ素微粉末を用意するステップと、累積破壊率６３．２％時の粒子強度が５．０ＭＰａ以上、平均粒径が２０μｍ以上１００μｍ以下、Ｘ線回折から求められる配向性指数の値が１０以下の、塊状窒化ホウ素微粉末を用意するステップと、窒化ホウ素微粉末と塊状窒化ホウ素粗粉末とを、塊状窒化ホウ素微粉末の含有割合が７質量％以上５０質量％以下の範囲となるようにして混合し、塊状窒化ホウ素粉末を得るステップとを含む、塊状窒化ホウ素粉末の製造方法。【選択図】なし