Survey of Inorganic Pigments

16 августа, 2015

Pokraskin

When we consider a short survey of today’s major inorganic pigments, we are faced with the realization that the three major pigment families: titanium dioxide, carbon black, and iron oxides, accounting for more than 90% of the worldwide tonnage, as shown in Table 1.1, are all outside of our subject matter. They are well known to everyone, and have already been discussed in depth in recent handbooks [1, 2].

Further inspection of Table 1.1, however, reveals a selection of “high performance” pigments classified according to their chemical composition. In particular, the families of complex (or mixed) metal oxides, and functional pigments show a wide variety in their chemical composition.

Table 1.1 Inorganic pigments, classified by composition.

Elements	Carbon black	+
	Al-flakes	+
	Oxide coated Al, Zn/Cu flakes Zn-dust	+
	Nanoscale silicon	#
Oxides/hydroxides	Metal-oxide flakes TiO2 Fe2O3 FeOOH Fe3O4 Cr3O3 Pb3O4	+
Mixed metal oxides		+
	ZnFe2O4	+
	CoAl2O4 (Co, Ni, Zn)2TiO4	+
	Ti(Ni, Nb)O2	+
	Ti(Cr, Nb)O2	+

Table 1.1 Continued

Class	Pigment	High performance
Sulfides	ZnS ZnS/BaSO4 (lithopone) CdS	+
	Ce2S3	+
Oxide/nitride	(Ca, La)Ta(O, N)3	#
Chromates	Pb(Cr, S)O4 Pb(Cr, Mo, S)O4
Vanadates	BiVO3	+
Silicates	Na3Al6Si6O24S3 (ultramarine) Mica, SiO2 and glass-based effect pigments	+
Cyanides	KFe[Fe(CN)6]

Note: # not yet in industrial scale

In every pigment class illustrated, one will find at least one grade with a high performance characteristic, which may be the determining factor, or driver, for the end user to purchase this pigment in their application. It is self-evident, therefore, that degree of performance for a pigment depends on the demands imposed upon it for its intended application.

1.3