Surface sulfonation of solid particles such as carbon black or organic pigments to give products used in e.g. ink jet inks, uses sulfur trioxide gas obtained by combustion of sulfur

摘要

Production of sulfonated solid particles comprises: (i) burning of sulfur to form sulfur dioxide (SO2) gas; (ii) catalytically oxidizing the SO2 gas to sulfur trioxide (SO3) gas; and (iii) sulfonating a dry powder or granulate with the SO3 gas in a gas-solid reaction. Independent claims are also included for the following: (1) the sulfonated solid particles; (2) compositions comprising the solid particles (especially a pigment) and a medium; (3) method and apparatus for creating images, using the composition.