CARBON BLACK FOR PRINTING INK MD PRINTING INK COMPOSITION

摘要

PROBLEM TO BE SOLVED: To provide carbon black for printing ink exhibiting excellent pitch- blackness and gloss without requiring surface oxidation treatment, improved in dryness known as the shortcoming of surface oxidation treated carbon black, and having no yield value. SOLUTION: The carbon black is characterized in that (1) sol-gel transition point Wgel [wt.%]>=63/(0.28+effective volume ratioα), that (2) pH>4, and that (3) agglomerate diameter Dmod[nm]<140.