ALEXANDRIA, Va., Nov. 6 -- United States Patent no. 12,460,303, issued on Nov. 4, was assigned to MEC COMPANY LTD (Hyogo, Japan).
"Etching agent and method for producing circuit board" was invented by Yu Fukui (Hyogo, Japan), Daisaku Akiyama (Hyogo, Japan), Dai Nakane (Hyogo, Japan) and Kenji Nishie (Hyogo, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "The present invention includes an etching agent that selectively etches a copper layer of a processing target in which a noble metal layer containing a metal nobler than copper and the copper layer coexist, the etching agent including: a copper ion; one or more nitrogen-containing compounds selected from the group consisting of a heterocyclic compound h...