Heribert Offermanns, Merkstein, Germany, has found that chance played a role in the discovery of blue pigments, and names Berlin Blue, Cu Phthalocyanine, and YInMn Blue as examples.
Berlin Blue (FeIII4[FeII(CN)6]3) is a lightfast, deep-blue pigment also known as Prussian Blue, Persian Blue, Turnbull’s Blue, Milori Blue, or Vossen Blue. In 1706, Johann Jakob Diesbach, Berlin, Germany, discovered it by chance: In the preparation of the red dye Florentine lacquer from cochineal lice, alum, iron(II) sulfate, and potash, he replaced the latter with Johann Konrad Dippel’s “animal oil” (or bone oil, a nitrogenous by-product of the destructive distillation of bones) and was surprised to find that he obtained a blue dye instead of a red one.
Cu Phthalocyanine Blue (C32H16CuN8) is a bright, crystalline, synthetic blue pigment, and the most important blue pigment today. In 1927, Henri de Diesbach and Edmond von der Weid, Germany, discovered the dye. At Imperial Chemical Industries (ICI), Grangemouth, UK, enamel flaked off during the reaction of phthalic anhydride with ammonia in an enamel-lined iron kettle. The metal became bare and a blue dye formed at this point. It was found that dyes form when phthalonitrile is reacted with heavy metals. ICI developed a manufacturing process from this, which was used for industrial production starting in 1934.
YInMn Blue (YIn1−xMnxO3) is a lightfast, non-toxic, easy-to-produce pigment also known as Oregon Blue or Mas Blue. In 2009, it was accidentally discovered by Mas Subramanian, Oregon State University, Corvallis, USA, and his then Ph.D. student Andrew E. Smith when mixing indium oxide, manganese oxide, and yttrium oxide in various ratios and heating the mixtures.
- Blaue Zufallsstunde,
Nachr. Chem. 2021.