Coated magnesium oxide particles having high filling efficiency and high mass-productivity and suitable for a thermal conductive filler are provided, the coated magnesium oxide particles being coated magnesium oxide particles in which the surface of magnesium oxide particles is coated with at least one of a fatty acid and a fatty acid metal salt, and wherein X in relation to particles is defined as X=[a BET specific surface area diameter calculated from a BET specific surface area of the particles][D.sub.50 of the particles], provided that D.sub.50 is a particle diameter at 50% accumulation in a cumulative particle size distribution of the particles, the magnesium oxide particles having X of less than 0.2 and D.sub.50 of 5 to 100 m, and the coated magnesium oxide particles having X of 0.2 or more, D.sub.50 of 5 to 100 m, and oil absorption of less than 25 mL/100 g.

An electrode for an energy storage device includes carbon black particles having (a) a Brunauer-Emmett-Teller (BET) surface area ranging from 70 to 120 m.sup.2/g; (b) an oil absorption number (OAN) ranging from 180 to 310 mL/100 g; (c) a surface energy less than or equal to 15 mJ/m.sup.2; and (d) either an L.sub.a crystallite size less than or equal to 29 , or a primary particle size less than or equal to 24 nm.

A method of preparing hydrophobic porous silica includes adding an alcohol to a solvent in which a porous silica particle including a hydrophilic group is dispersed and stirring the same to form a mixture, drying the mixture including the porous silica particle in a vacuum, and condensation reacting the hydrophilic group of the porous silica particle with the alcohol on the surface of the porous silica particle to modify the surface of the porous silica particle to be hydrophobic.

Particles with suitable properties may be generated using systems and methods provided herein. The particles may include carbon particles.

An object of the present invention is to provide a carbon black, an ink, and the like having excellent dispersion stability. A carbon black of the present invention includes iron element in an amount of 0.01 to 2.00 parts by mass per 100 parts by mass of the carbon black. Preferably, a ratio of Fe/C is 0.001 to 0.010, where Fe is a concentration in atomic % of the iron element on a surface of particles of the carbon black, and C is a concentration in atomic % of elemental carbon on the surface of the particles of the carbon black, as determined by X-ray photoelectron spectroscopy.

Carbon black in which an oil absorption amount is 150 mL/100 g or more and 400 mL/100 g or less and an iron content that is measured by induced coupled plasma-mass spectrometry is 500 ppb or less.

Carbon black in which an oil absorption amount is 150 mL/100 g or more and 400 mL/100 g or less and a nickel content that is measured by induced coupled plasma-mass spectrometry is 50 ppb or less.

The present invention relates to a filler for a paint composition, wherein the filler comprises a calcinate having particles with an average particle size (d.sub.50, SediGraph III) in the range between 3 m and 50 m and a mullite content of 30-70 measured as mullite index. The invention is characterised in that the bulk density of the filler is >450 g/L. The invention also relates to a paint composition characterised in that it comprises a filler which has a bulk density>450 g/L and comprises a calcinate which has particles with a mean particle size (d.sub.50, SediGraph III) in the range between 3 m and 50 m and a mullite content of 30-70 measured as mullite index. Furthermore, the invention relates to uses of such a filler for the preparation of a paint composition.

Carbon black for use in elastomeric compositions, together with methods for the manufacture and use thereof.

Carbon nanostructures are used to prepare electrode compositions for lithium ion batteries. In one example, carbon nanostructures, fragments of carbon nanostructures and/or fractured carbon nanotubes are provided in an aqueous dispersion that can be used in the manufacture of silicon-containing anodes. The aqueous dispersion can further include another conductive carbon additive such as carbon black.