Bakelite radio. A 1936 Philco 444 British-made radio with bakelite casing. Wireless telegraphy, the principle upon which radios operate, was developed by Guglielmo Marconi from 1895. The first portable radio receiver was invented in 1922. Bakelite, the first commercially successful plastic, was discovered in the 1920's by the Belgian-born chemist Leo Baekeland whilst he was doing research on synthetic varnishes in the U.S. It is a thermosetting plastic (it does not melt once it has been heated and set) and a good insulator. It was therefore the ideal material for casings for electrical devices such as telephones and radios.