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Toshiyuki Nagasawa: Water-based pigment ink and process for producing the same. Orient Chemical, Birch Stewart Kolasch & Birch, March 11, 1997: US05609671 (138 worldwide citation)

Water-based pigment ink having high concentration which provides excellent jetting stability when using for ink-jet printer and provides excellent writing stability when using for fine-point pen was provided.


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Nagasawa Toshiyuki: Water-based pigment ink and process for producing the same. Orient Chemical, December 27, 1995: EP0688836-A2 (51 worldwide citation)

A water-based pigment ink having high concentration which provides excellent jetting stability when using for ink-jet printer and provides excellent writing stability when using for fine-point pen is provided. The water-based pigment ink comprises water and carbon black, wherein said carbon black ha ...