| 摘要 |
PROBLEM TO BE SOLVED: To prevent cracking and breakage at the time of molding and produce a molded product having stabilized density and dispersibility at the time of use by controlling a true pressure applied to a carbon black powder according to a specific method when carrying out the pressure molding of the carbon black. SOLUTION: When carbon black 9 is placed in a space formed from a die 5 and two punches 4 and 6 and the pressure molding is carried out, the surface pressure of the punch 6 on the side opposite to a pressurizing source is increased to a desired surface pressure while detecting the surface pressure of the punch 6. The surface pressure of the punch 6 is zero at the beginning of the start of the pressurizing but is gradually increased to become constant. The surface pressure at this point of time is the final one and the pressurizing is performed so that the final surface pressure reaches preferably 2-500 kg/cm2. The density of the molded product of the carbon black is preferably <=1.0 g/cc. |
