Patent ID: 8172916

Claim:
A diamond powder consisting of fine diamond particles, wherein; (i) said diamond powder has an element composition consist mainly of carbon in the range of 72 to 89.5% by weight, hydrogen in the range of 0.8 to 1.5%, nitrogen in the range of 1.5 to 2.5%, and oxygen in the range of 10.5 to 25.0%, (ii) and, particles of said powder have a narrow distribution of diameters thereof so as to range in the scope of 150 to 650 nm by number average particle diameter (ØMn), and particles of over 1000 nm and below 30 nm in the diameter are absent, (iii) and, particles of said powder exhibit a strongest peak of the intensity of the Bragg angle at 43.9° (2θ±2°), strong and characteristic peaks at 73.5° (2θ±2°) and 95° (2θ±2°, a warped halo at 17° (2θ±2°), and no peak at 26.5°, by X-ray diffraction (XRD) spectrum analysis using Cu—Kα radiation, (iv) and, the specific surface area of said powder is not smaller than 1.50×10 5 m 2 /kg, and substantially all of the surface carbon atoms of said particles are bonded with hetero atoms, and total absorption space of said powder is 0.5 m 3 /kg or more.