Complex inorganic color pigment

The three main groups of commercial complex inorganic color pigments are titanates, which use a titanium dioxide base, aluminates, which use an aluminum oxide base, and chromites and ferrites, which have chromium and/or iron oxide bases. Some important complex inorganic color pigments are listed in Table 3.4. 

Certain chromite type complex inorganic color pigments are suitable for use in camouflage paints and in low heat buildup paints due to their specific infrared reflectance properties. Due to their non-toxic 

Pigment (Cl name) Metal composition Color Crystal structure 

Pigment Blue 36 Co, Cr, Al Blue-green to teal green Spinel 

The rule implied that these two metals had somehow become PBTs. The EPA was considering lowering the reporting thresholds under the TRI for cobalt and listing all compounds of vanadium as TRI reporting substances in the future. It is interesting to note that the proposal specifically exempted alloys, such as steel, containing cobalt and vanadium. 

The final rule listed bismuth vanadate, as a vanadium compound, as a TRI compound for annual reporting [9]. The mlemaking did not include a reasonable argument for the bioaccumulation of either cobalt or vanadium metals included in insoluble compounds. Nor was there any mention of cobalt blue or vanadium yellow pigments. 

The final PBT-TRI rule did not change the TRI reporting requirements for cobalt Vanadium compounds were added to the list of TRI reportable substances. Reporting thresholds are the same as other substances, 10 000 pounds for chemicals processed or otherwise used or 25 000 pounds for manufactured compounds. 

OECD-HPV testing is now underway for nickel antimony titanate. It is our understanding that mammaUan development and toxicity testing are now complete and preliminary results show no toxicity. 

The Minnesota Listed Metals Advisory Council (LMAC) has completed its review of color pigments under the Toxics in Specified Products Law. The LMAC voted unanimously in favor of not banning the use of complex inorganic color pigments, lead chromate pigments and cadmium pigments. Specific LMAC reviews of many paint and ink products were also completed in 2000. These include automotive paints, architectural and maintenance coatings. 

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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. 

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. 

Complex inorganic colored pigments are solid solutions or compounds consisting of two or more metal oxides. One oxide serves as a host and the other oxide(s) inter-diffuse into the host crystal lattice. This interdiffusing is accomplished at temperatures generally in excess of 1000°C. Of the 14 possible crystal structures, the two most important for plastics applications are rutile and spinel. A third structure, zircon, will be briefly mentioned. 

In terms of fastness properties, complex inorganic colored pigments are unequaled. Their high calcination temperatures during manufacture impart thermal stabilities up to 1000°C, outstanding outdoor durability, and outstanding chemical resistance. 

Meteor, Complex inorganic color pigments, Engelhard Corp. 

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