When did the felt tip pen become popular?

The felt tip pen became popular in the 1960s, particularly after the introduction of the first commercially successful version, the Flair pen, in 1966. Its ease of use, vibrant ink options, and versatility made it a favorite among artists, students, and professionals. The rise of felt tip pens paralleled the growth of the art and design movements during that decade, further solidifying their place in everyday writing and drawing tools.