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QuickNote: What Makes Paper Fountain Pen Friendly?

The other way manufacturers create fountain pen friendly paper is through a specific finish. In Clairefontaine’s case, vellum finished paper (what’s used in their notebooks) adds significant resistance to feathering and bleedthrough and for a more extreme example, Tomoe River paper has a silky smooth finish that resists ink, causing it to dry on the surface rather than leeching down.

Source: What Makes Paper Fountain Pen Friendly?