Johnny Sokko and His Flying Robot: 5 - The Gigantic Claw

Giant Robo (ジャイアントロボ, Jaianto Robo), also known as Johnny Sokko and His Flying Robot in the United States, is a manga and tokusatsu series created by Mitsuteru Yokoyama. It is similar to Yokoyama's Tetsujin 28-go (known as Gigantor in the U.S.), but Giant Robo has more elements of fantasy. The original 26-episode tokusatsu TV series, produced by Toei Company, aired on NET (later renamed TV Asahi) from October 11, 1967 to April 1, 1968.
In this episode Dr. Tadokora develops QQV, a super-strong transparent metal. He tests it and QQV endures all the attacks of Giant Robo. The BF Syndicate (Gargoyle Gang in American version) watch the experiments using TV cameras and try to steal the specifications of QQV.