Inktend / Ink library / Ku-jaku
Pilot Iroshizuku
Ku-jaku
Blues & navies
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A premium Japanese ink line named after natural imagery — each color takes its name from a scene like moonlight, autumn leaves, or morning glory.
Specs
Color familyBlues & navies
Approx. hex#14727E
SheenNot typically noted
BrandPilot Iroshizuku
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About Pilot Iroshizuku
Iroshizuku is Pilot's premium ink line, launched to critical acclaim in the early 2010s — each color is named after a scene from nature, from moonlight (Tsuki-yo) to autumn leaves (Momiji).
Japan
Founded 2010s
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Paper & pairing notes
Blues and navies are the most broadly "safe" fountain pen colors — legible, professional, and unlikely to raise eyebrows in an office. This ink will behave predictably on most fountain-pen-friendly paper. Cheap, highly absorbent paper (standard copier paper) will dull any ink's saturation and can cause feathering or bleed-through with wetter nibs.
Storing and using the bottle
Bottled fountain pen ink has an effectively long shelf life when kept capped and out of direct sunlight — most inks remain usable for years. The main risk isn't the ink spoiling, it's a pen sitting inked and unused for weeks: that's what causes clogs, not the ink's age.
Frequently asked questions
What color family is Ku-jaku?
Ku-jaku falls into Inktend's blues & navies family based on its typical swatch color.
Does Ku-jaku have sheen?
Ku-jaku is not typically noted for sheen. If you want that effect, browse similarly colored inks tagged with sheen in the ink library.
How should I store a bottle of Ku-jaku?
Bottled fountain pen ink has an effectively long shelf life when kept capped and out of direct sunlight — most inks remain usable for years. The main risk isn't the ink spoiling, it's a pen sitting inked and unused for weeks: that's what causes clogs, not the ink's age.
What paper works best with Ku-jaku?
Blues and navies are the most broadly "safe" fountain pen colors — legible, professional, and unlikely to raise eyebrows in an office. This ink will behave predictably on most fountain-pen-friendly paper. Cheap, highly absorbent paper (standard copier paper) will dull any ink's saturation and can cause feathering or bleed-through with wetter nibs.
Similar shades
Color shown is a close digital approximation of a typical swatch, not a calibrated color match.