Complex inorganic pigments

The color of complex inorganic pigments results from the incorporation of cations of transition metals into the crystal of the host oxides. The host can be a single oxide such as Ti02 (rutile) or a mixed oxide such as TiZn204 (spinel) or MgAl204 (spinel). Most of the host oxides can be found as naturally occurring... 

All rutile pigments are derived from the rutile titanium dioxide structure. Rutile forms of complex inorganic pigments are by far the most commonly used in plastics. The following are among the most widely used ... 

Some of the inorganic pigments used are based on heavy metals (e.g., barium, cadmium, iron, lead, mercury/chromium oxides, titanium, zinc, complex inorganic pigments as mixtures of two or more metal oxides, and sulfides), or they can be metals themselves (e.g., aluminium, copper, gold), dispersed as powders into the plastic bulk. 

Geode, Complex inorganic pigments, Eerro Corp., Color Div. 

Heuco Pigments, Organic pigments, Heucotech Heucodur, Complex inorganic pigments, Heucotech... 

Kerafast, Cobalt, complex inorganic pigment, Johnson Matthey, Pigments Dispersions... 

Mixed-Metal Oxide Pig ments. Mixed-metal oxide pigments can be considered a subcategory of complex inorganic color pigments. The name, mixed-metal oxides, does not, however, represent the reaUty as these pigments are not mixtures but rather soHd solutions or compounds consisting... 

Complex Inorganic Color Pigments Committee, Tdry Color Manufacturer s Msociation, 3rd ed., DCMA, Alexandria, Va., 1991. 

Although it might seem at first sight that dyestuffs are merely held mechanically within the pores, and this view is probably correct in the case of inorganic pigments, there is some support for the opinion that only those dyestuffs which form aluminium/metal complexes produce really light-fast colorations. 

As shown in the previous sections, identifying a small amount of a protein (in the order of tens of picomoles) represents a difficult problem for traditional methods of chemical analysis. The situation is even more complicated when a protein mixture of variable composition should be identified in a complex matrix containing dyes, oils, inorganic pigments, lime, etc. moreover, the analysed materials come often from the Middle Ages or even ancient times and the proteins in them could have undergone various modifications (e.g. oxidation, photodecomposition and microbial digestion) over the centuries. 

Two types of insoluble triarylcarbonium compounds are used industrially as pigments. Both are salts of these basic dyes. So-called Alkali Blue type triarylcarbonium pigments are inner salts of sulfonic acids, while the second group comprises salts of complex inorganic anions of heteropolyacids. 

This class of pigments consist of salts of the anions of complex inorganic acids with dye cations, primarily with triarylcarbonium cations. 

The term mixed metal oxide pigment denotes a pigment that crystallizes in a stable oxide lattice, and in which the color is due to the incorporation of colored cations in this lattice. Such compounds are regarded as solid solutions. The American Dry Color Manufacturers Association has abandoned the term mixed metal oxide inorganic colored pigments , it denotes these colorants as complex inorganic color pigments [3.73],... 

DCMA Classification and Chemical Description of the Complex Inorganics Color Pigments, 3rd. ed., Dry Color Manufacturers Association, Alexandria, Virginia, 1991. 

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