Question: how long has tcp been around?
Answer: TCP was introduced in 1918. The brand name comes from its original chemical name, which was trichlorophenylmethyliodosalicyl (not to be confused with trichlorophenol, a common fungicide). Trichlorophenylmethyliodosalicyl was replaced as the active ingredient by a mixture of phenol and halogenated phenols in the 1950s.