窒化ホウ素

化学的特性white powder(s), 1μm or less 99.5% pure; hexagonal, most common form: a=0.2504 nm, c=0.6661nm; fcc: a=0.3615nm; hardness: hexagonal like graphite,cub approaches that of diamond; band gap ~7.5 eV at 300K; dielectric 7.1; used in furnace insulation and in crucibles for melting aluminum, boron, iron, and silicon, also as sputtering target for dielectrics, diffusion masks, passivation layers [KIR81] [HAW93] [MER06] [CER91]

化学性质低結晶性のBNは乱層構造（t-BN）で，高温で結晶性の高いh-BNとなる。h-BNはグラファイト類似構造で，BN六角網面が積層した構造である。

解説プラズマ放電でBNナノチューブが合成され，カーボンナノチューブより高温空気中の安定性が高いため，電子放出用電極材としての開発が進められている．h-BNは無色の結晶．密度2.34 g cm－3．耐熱性が大きいが2500 ℃ 付近から昇華がはじまる．融点約3000 ℃．電気絶縁性は大きい(比抵抗 107 Ω m)．耐化学薬品性も大きく，とくに酸に強い．熱アルカリ，溶融炭酸アルカリには急速に侵される．空気中では1100 ℃ 付近までは侵されないが，1200 ℃ 以上では徐々に酸化される．不活性気体中では2000 ℃ 以上まで耐える．水蒸気と加熱すると900 ℃ 以上で分解する．c-BNは無色の結晶．密度3.45 g cm－3．モース硬さ10で，ダイヤモンドにきずをつけることができる．物性および化学性はh-BNに準じる．森北出版「化学辞典（第2版）

用途合金の製造。半導体。原子炉。潤滑油。断熱用炉材。るつぼ。化学装置材料。

説明Boron nitride is a material in which the extra electron of nitrogen (with respect to carbon) enables it to form structures that are isoelectronic with carbon allotropes.Boron nitride is an inorganic compound with a flat, hexagonal crystal similar to graphite, but with the carbon atoms replaced by boron and nitrogen atoms. The alternate boron and nitrogen atoms are linked to form interlocking hexagonal rings with three boron atoms and three nitrogen atoms, and the layers are held together by van der Waals forces. There is no boron-nitrogen bonding between the layers.The bond length is 1.466Å and the interlayer spacing is 3.331 Å. A spherical form (with a hexagonal crystal structure) is also available.Boron nitride can also be in cubic form in which alternately linked boron and nitrogen atoms form a tetrahedral bond network, similar to carbon atoms in diamond.

使用Boron nitride is a material in which the extra electron of nitrogen (with respect to carbon) enables it to form structures that are isoelectronic with carbon allotropes. Also used in manufacture of alloys; in semiconductors, nuclear reactors, lubricants.Hexagonal boron nitride can be used as an electrical insulator; as thermocouple protection sheaths, crucibles and linings for reaction vessels; and as a coating for refractory molds used in glass forming and in superplastic forming of titanium. It can also be incorporated in ceramics, alloys, resins, plastics, and rubber to give them self-lubricating properties. Hexagonal boron nitride is used the formulation of coatings and paints for high temperature applications. It is also used as a substrate for semi-conductors, lens coatings, and transparent windows. https://www.cir-safety.org

一般的な説明Boron nitride in cubic form, known as Borazon, is a manufactured abrasive that was discovered by General Electric Co. Laboratories in 1957. Unlike manufactured diamond, Borazon does not have a natural counterpart. It is produced under temperatures and pressures similar to those required for diamond manufacture. Additionally, cubic boron nitride exhibits greater thermal stability compared to diamond. It remains stable at temperatures exceeding 1,371°C, while diamond reverts to graphite at temperatures above 816°C. Borazon has a Knoop hardness (K100) of 7800, which is higher than ordinary abrasives but lower than diamond.

使用用途窒化ホウ素は、熱伝導性や電気絶縁性に優れていることから、放熱樹脂シートや放熱基板用のフィラーとして幅広く使用されます。 耐熱性や耐食性、潤滑・離型性にも優れた材料であるため、各種マトリックスへの添加材としても使用されています。具体的な用途の例として、各種放熱材料の添加材、、オイル添加材、高温潤滑添加材等が挙げられます。また、各種金属・の耐熱離型材や溶融金属保護コーティング材等としても使用されております。 感触改良やを目的として、メイクアップ化粧品や日焼け止め製品等にも、窒化ホウ素が使用されることもあります。

In tonnage production, acetaldehyde may be manufactured by: 1. The direct oxidation of ethylene, requiring a catalytic solution of copper chloride plus small quantities of palladium chloride Cl2Pd. 2. The oxidation of ethyl alcohol C2H6O with sodium dichromate Cr2Na2O7, and 3. The dry distillation of calcium acetate C4H6CaO4 with calcium formate C2H2CaO4.

製造方法Boron nitride is prepared by heating boric oxide with ammonia: B2O3 + 2NH3 → 2BN + 3H2O Alternatively, the compound can be prepared by heating boric oxide or boric acid with ammonium chloride or an alkali metal cyanide. Purified product can be obtained by high temperature reaction of boron halide with ammonia: BCl3 + NH3 → BN + 3HCl Boron nitride can also be made from the elements by heating boron and nitrogen at red heat.

合成方法還元窒化法，化学析出法，高圧合成法で製造される。

定義本品は、次の化学式で表される無機顔料である。

定義boron nitride: A solid, BN, insolublein cold water and slowly decomposedby hot water; r.d. 2.25 (hexagonal);sublimes above 3000°C. Boronnitride is manufactured by heatingboron oxide to 800°C on an acid-solublecarrier, such as calcium phosphate,in the presence of nitrogen orammonia. It is isoelectronic with carbonand, like carbon, it has a veryhard cubic form (borazon) and asofter hexagonal form; unlikegraphite this is a nonconductor. It isused in the electrical industrieswhere its high thermal conductivityand high resistance are of especialvalue.