Founded in Tokyo in 1912 by craftsmen who trained under Sadajiro Sasaki* himself, Sase Kogyosho (佐瀨工業所) stands as the oldest workshop in Japan to preserve the tradition of the original glass pen-making. Through three generations, the workshop has maintained an unwavering commitment to technical mastery and meticulous handcraft. From the Meiji to the Showa era, Sase Kogyosho’s artisans perfected the technique of creating the elegant grooves and twists in glass with precision, a skill requiring years—sometimes decades—of dedicated practice.

Currently, Yoshihiro Rachi is the head of Sase Kogyosho, the third generation owner who learned the skills and inherited the workshop of his father-in-law, the late Isamu Sase, and carries on the tradition of handcrafting glass pens one by one.

*- The glass pen is said to have been developed by Sadajiro Sasaki, a wind chime craftsman in the late Meiji era (1868-1912). Sase Kogyosho, established in Taito Ward, Tokyo, in 1912, is said to be the only glass pen factory that currently still employs Sasaki’s techniques.