US Patent Issued to MITSUBISHI PENCIL on Feb. 24 for "Coloring tablet and water-based ink composition for writing instrument using the same" (Japanese Inventors)

ALEXANDRIA, Va., Feb. 24 -- United States Patent no. 12,559,637, issued on Feb. 24, was assigned to MITSUBISHI PENCIL COMPANY Ltd. (Tokyo).

"Coloring tablet and water-based ink composition for writing instrument using the same" was invented by Tatsuya Mizoguchi (Tokyo) and Takayuki Ikai (Tokyo).

According to the abstract* released by the U.S. Patent & Trademark Office: "A coloring tablet may have excellent solubility and redispersibility and a water-based ink composition for a writing instrument. Such a coloring tablet may contain at least a colorant and a dispersing agent. The dispersing agent may include a hydroxide neutralization product of an (meth)acrylic resin, a hydroxide neutralization product of a styrene-maleic acid copolymer re...