Inventor
IKAI TAKAYUKI
JP11 patents
Patents
11 patentsUS5942027AAug 24, 1999
Ink for ball point pen
MITSUBISHI PENCIL CO51 citations90
US6830611B2Dec 14, 2004
Oil-base ink composition, writing utensils and dyes to be used therein
MITSUBISHI PENCIL CO9 citations69
US10569596B2Feb 25, 2020
Writing tool refill and writing tool using same
MITSUBISHI PENCIL CO5 citations64
US11135868B2Oct 5, 2021
Refill for writing implements and writing implements using the same
MITSUBISHI PENCIL CO0 citations60
US6441061B1Aug 27, 2002
Additive for oil-based ink for a ball point pen and oil based ink for a ball point pen containing the same
MITSUBISHI PENCIL CO6 citations60
US7381754B2Jun 3, 2008
Oil-based ink composition and uses thereof
MITSUBISHI PENCIL CO4 citations58
US12559637B2Feb 24, 2026
Coloring tablet and water-based ink composition for writing instrument using the same
MITSUBISHI PENCIL CO0 citations57
US12054622B2Aug 6, 2024
Oil-based ink composition for writing utensils, writing utensil using same, and airbrush unit using same
MITSUBISHI PENCIL CO0 citations55
US6945726B2Sep 20, 2005
Refill for oil-based ink ballpoint pen and oil-based ink ballpoint pen
MITSUBISHI PENCIL CO6 citations54
US7311459B2Dec 25, 2007
Follower for non-aqueous ball point pen and non-aqueous ball point pen
MITSUBISHI PENCIL CO1 citations51
US11654711B2May 23, 2023
Writing tool provided with refill
MITSUBISHI PENCIL CO0 citations50