In 1962, Yukio Horie of the Tokyo Stationery Company patented a felt-tipped pen. This was a significant step in the development of the modern marker pen. The design used a felt tip that delivered ink evenly and consistently, making it a reliable tool for writing and drawing.

The felt-tipped pen offered poets a new medium for creative expression. Its bold, colorful, and expressive lines were ideal for visual and concrete poetry. The marker pen allowed for a more graphic and bold approach to lettering, influencing the visual aesthetic of poetry in the mid-to-late 20th century.