A patent for "Methods and Means of Defrosting a Cold Diffuser" was issued to its Black American inventor, F.M. Jones (No. 2,666,298). It gave a method to defrost using a heating medium when the surface of the diffuser has accumulated a layer of frost or ice which would otherwise reduce its heat transfer capacity. He used a compressor, condenser and evaporator which were interconnected in a manner such that the compressed refrigerant could also accomplish the defrosting of the evaporator in a defrosting cycle. He was a prolific inventor, whose first patent was for a "Ticket Dispensing Machine" in 1939 (No. 2,163,754), accumulating about 20 more patents relating to gas engines and refrigeration devices in 20 years.

A U.S. patent was issued to George Claude of Paris titled a “System of Illuminating by Luminescent Tubes” which led to the neon sign (No.1, 125,476). The patent describes the technical details to be observed in the construction of a tube well evacuated of other gases before the addition of one of the rare gases, especially neon. It considered the materials used and size of the electrodes, the diameter of the tube, and suitable operating pressure. Tube lengths of 5 to 6 meters were discussed, and how it was possible to maintain the light output for an extensive used life.