Question from Harold G.:
Who figured out the ammonium nitrate instant ice packs first? Did they patent it?
-Harold G.
Albert A. Robbins applied for an application for chemical freezing packs on June 15, 1956. He received US Patent 2,898,744 on August 11, 1959. The patent was assigned to Kwik-Kold of America. Kwik-Kold brand instant ice packs are still manufactured and sold by Cardinal Health.
View the patent for the instant ice pack here.