Environmentally benign inorganic red pigments based on tetragonal β-Bi2O3. (January 2019)

• Record Type: Journal Article
• Authors: Gramm, Georg; Fuhrmann, Gerda; Wieser, Martin; Schottenberger, Herwig; Huppertz, Hubert
• Is Part Of: Dyes and pigments. Volume 160(2019)
• Page Start: 9
• Page End: 15
• Publication Date: 2019-01
• Subjects: Bismuth oxide -- Red inorganic pigment -- Solid state reaction -- Heterometallic bismuth oxides; Dyes and dyeing -- Periodicals; Pigments -- Periodicals; 667.2
• DOI: 10.1016/j.dyepig.2018.07.039
• Languages: English
• ISSNs: 0143-7208

Abstract

Abstract: This paper reports on the synthesis, characterization, and optical properties of a new class of environmentally friendly red pigments based on the tetragonal β-phase of Bi2 O3 . Stabilization of the metastable β-phase at room temperature has been successfully achieved through incorporation of various metal cations ( M = Y 3+, Zr 4+, Eu 3+, Nb 5+ ). Doping with zirconia (Zr 4+ ) yielded compounds showing the most promising red color coordinates ( a * > 30) with the best value provided by the composition. Subsequently, this specific intermediate of the β-phase was further reacted with FeOOH to generate, under preservation of the β-Bi2 O3 -type structure, a red product with the formula (Bi1.95 Zr0.05 )0.8 Fe0.4 O3+ δ . With color coordinates of L * = 49.9, a * = 31.1, and b * = 25.8, the newly developed pigment has been found to be superior compared to the conventional Fe2 O3 pigment (Bayferrox 4130: L * = 37.4, a * = 28.9, and b * = 20.8). Highlights: New class of environmentally friendly red pigments based on the tetragonal β-phase of Bi2 O3 . Red compound (Bi1.95 Zr0.05 )0.8 Fe0.4 O3+ δ with color coordinates of L * = 49.9, a * = 31.1, and b * = 25.8. Superior compared to the conventional Fe2 O3 pigment.