US Patent Issued to KANTO KAGAKU on April 14 for "Etching solution and etching method for gold or gold alloy" (Japanese Inventors)

ALEXANDRIA, Va., April 15 -- United States Patent no. 12,600,908, issued on April 14, was assigned to KANTO KAGAKU K.K. (Tokyo).

"Etching solution and etching method for gold or gold alloy" was invented by Itsuki Kashiwagi (Tokyo), Yuki Yoshida (Tokyo), Koichi Inoue (Tokyo) and Iori Kawashima (Tokyo).

According to the abstract* released by the U.S. Patent & Trademark Office: "It is known that when etching gold films using etching solutions containing iodine and iodide, N-methyl-2-pyrrolidinone (NP) is added to improve the etching solution's wettability, microfabrication property, and solution life. However, in recent years, the use of NMP has been regulated due to its adverse effects on human health. The present invention provides an etch...