| abstract |
A packing material for liquid chromatography is produced by mixing 1.0 part by weight of carbon black, 0.5 to 2.5 parts by weight of one or a mixture of a synthetic resin which can be graphitized by heating and a toluene- or benzene-soluble component of pitches, and an organic solvent to obtain a mixture. The carbon black has a particle diameter of 12 to 40 nm, a specific surface area of 50 to 650 m²/g, a DBP oil absorption amount of 50 to 150 ml/100g. The synthetic resin is one selected from phenol resin, furan resin, furfural resin, divinylbenzene resin and urea resin. The pitches are ones selected from petroleum pitches, coal-tar pitches and liquefied coal oil. The mixture is granulated by spray granulation or emulsion granulation to obtain granules whose ratio L min /L max of a minor axis diameter L min to a major axis diameter L max is 0.90 to 1.0. The heat treatment of the granules is also made in an inert gas under pressure. |