noun
printing ink
Refers specifically to ink used in printing processes, as opposed to writing ink (インク).
この印刷インキは速乾性です。
This printing ink is quick-drying.
インク is a general term for ink, including writing ink, while 印刷インキ specifically means printing ink.
Compound of 印刷 (printing) and インキ (ink, from English 'ink').