Patent GB-947261-A (GB)
Title: Improvements in method of treating carbon black
IPC: C08K3/04
Filed: 1962-05-07
Abstract: High structure carbon blacks are fed to an enclosed milling chamber, partially filled with hard surface objects, and the chamber with its contents is subjected to rapid vibratory motion, thus effecting by detritioning action a reduction in the chain structure of the carbon blacks. The high structure carbon black may be a furnace black produced from a liquid aromatic hydrocarbon. The hard surface objects may be steel balls having a Rockwell C hardness of at least 55 and a diameter ranging from 1/16 inch to 1 inch.  The weight ratio of balls to carbon black charged to the milling chamber is between 40 : 1 and 350 : 1 and balls of various diameters within the range stated above may be used. The milling chamber shell is vibrated at a frequency of between 500 and 5000 vibrations per minute with an amplitude of between 1/8 inch and 3/4 inch.  Milling may be carried out in various atmospheres, e.g. sulphur dioxide, chlorine, in order to modify surface characteristics of the carbon black.  The processing time required to treat a carbon black to a particular quality level may be reduced from 24 hours to 1 to 2 hours by using batchwise vibratory milling instead of rotary ball milling, further reduction in time being obtainable if continuous vibratory milling is used. Tables giving the physical and chemical properties and rubber compounding characteristics of a high structure carbon black treated in both rotary and vibratory ball mills are shown compared with the properties of the black before such treatment. Specifications 813,162 and 838,009 are referred to.ALSO:High structure carbon blacks are fed to an enclosed milling chamber, partially filled with hard surface objects, and the chamber with its contents is subjected to rapid vibratory motion, thus effecting by detritioning action a reduction in the chain structure of the carbon blacks.  The high structure carbon black may be a furnace black produced from a liquid aromatic hydrocarbon.  The hard surface objects may be steel balls having a Rockwell C hardness of at least 55 and a diameter ranging from 1/16 inch to 1 inch.  The weight ratio of balls to carbon black charged to the milling chamber is between 40 : 1 and 350 : 1 and balls of various diameters within the range stated above may be used.  The milling chamber shell is vibrated at a frequency of between 500 and 5000 vibrations per minute with an amplitude of between 1/8 inch and 3/4 inch.  Milling may be carried out in various atmospheres, e.g. sulphur dioxide, chlorine, in order to modify surface characteristics of the carbon black.  The processing time required to treat a carbon black to a particular quality level may be reduced from 24 hours to 1 to 2 hours by using batchwise vibratory milling instead of rotary ball milling, further reduction in time being obtainable if continuous vibratory milling is used.  Tables giving the physical and chemical properties and rubber compounding characteristics of a high structure carbon black treated in both rotary and vibratory ball mills are shown compared with the properties of the black before such treatment.  Specifications 813,162 and 838,009 are referred to.