ALEXANDRIA, Va., June 25 -- United States Patent no. 12,339,620, issued on June 24, was assigned to CANON K.K. (Tokyo).
"Toner" was invented by Maki Imura (Chiba, Japan), Tomoyo Miyakai (Tokyo), Kentaro Kamae (Kanagawa, Japan), Yuu Nishimura (Chiba, Japan), Shin Kitamura (Ibaraki, Japan) and Takaho Shibata (Tokyo).
According to the abstract* released by the U.S. Patent & Trademark Office: "A toner, comprising a toner particle comprising a binder resin and a water-soluble polyvalent metal salt, wherein a main component of the binder resin is a polyester resin having specific acid value, the water-soluble polyvalent metal salt is a chloride, nitrate or sulfate of the specific metal, the water-soluble polyvalent metal salt has a solubility i...