The first acrylic acid was created in 1843. Methacrylic acid, derived from acrylic acid, was formulated in 1865. The reaction between methacrylic acid and methanol results in the ester methyl methacrylate. In 1877 the German chemist Wilhelm Rudolph Fittig discovered the polymerization process that turns methyl methacrylate into polymethyl methacrylate. In 1933, the brand name "Plexiglas" was patented and registered by another German chemist, Otto Röhm. In 1936 Imperial Chemical Industries (now Lucite International) began the first commercially viable production of acrylic safety glass. During World War II both Allied and Axis forces used acrylic glass for submarine periscopes and aircraft windshields, canopies, and gun turrets. Airplane pilots whose eyes were damaged by flying shards of PMMA fared much better than those injured by standard glass, demonstrating the much-increased compatibility between human tissue and PMMA as compared to glass.[4]