Eboya Kobue Shinkai Deep Sea Fountain Pen
Eboya is the last remaining manufacturer of ebonite in Japan. Each pen reflects a deep commitment to traditional craftsmanship and refined material expertise. Ebonite —one of the earliest polymers— is made by vulcanizing natural rubber with sulfur (25% to 50%), resulting in a material known for its strength and unique natural luster. Its name derives from “ebony” and was originally used as a substitute for wood in precision applications. Every pen body is engraved with Eboya Made in Tokyo, a mark of origin and authenticity.
Design and inspiration
The Kobue model, meaning “little flute,” is one of the most recent creations from Eboya. Its silhouette is defined by two continuous curved lines that form an elegant, ergonomic profile. The design is clipless, enhancing the pen’s minimalist and fluid shape. The Shinkai finish —meaning “deep sea”— blends translucent dark blue with irregular black streaks, evoking ocean currents and depth. Each pen is turned from a unique block of ebonite, ensuring no two pieces are ever alike.
Functionality and filling system
Fitted with a carefully tuned 14K gold nib crafted by the artisans at Nikko Ebonite Manufacturing, the Kobue delivers a smooth and well-balanced writing experience. It uses a standard international cartridge or converter, compatible with brands such as Pelikan or Rotring (not compatible with Montblanc, Waterman, or Caran d’Ache). Every pen is hand-polished and assembled in Tokyo with precision. The perfect alignment of its components, paired with the natural depth of its color, makes this pen a work of both beauty and precision.
Package contents
• Eboya Kobue Shinkai Deep Sea fountain pen
• Standard international converter
• Ink cartridge (1 unit)
• Paulownia wood box (At Inktraveler, all Eboya pens are delivered in a paulownia wood box instead of the brand’s standard cardboard packaging, a format usually reserved for premium orders in Japan.)
• Warranty
(Photos are for reference and may slightly differ from the actual product.)
Technical specifications
- Body material: ebonite
- Color: translucent dark blue with black streaks (Shinkai)
- Closed length: 125 mm
- Open length: 129 mm
- Body diameter: 13 mm
- Nib: 14K gold
- Filling system: international cartridge/converter
- Made in Tokyo, Japan
Care and maintenance
Keep away from direct sunlight or excessive humidity. Occasional cleaning with a soft dry cloth is enough to maintain its natural beauty.
Brand philosophy and history
Eboya is the flagship brand of Nikko Ebonite Manufacturing, founded in 1952 and known as Japan’s last specialist in ebonite production. For decades, it has supplied this material to leading pen companies like Sailor and Pilot. In 2009, the company launched its own range of writing instruments, blending technical know-how with Japanese aesthetic sensibility. Until 2016, production was led by master turner Noritoshi Kanesaki, a disciple of the renowned nibmeister Kubo Kohei. Today, Eboya continues to produce pens that are functional, long-lasting and visually distinctive.
"A writing instrument that blends Japanese spirit with exceptional craftsmanship."
