Pages: 19 Published: Jan 2012
ALMOST EVERYTHING MANMADE THAT IS WHITE or light in color contains white pigment in its surface: houses inside and outside, industrial articles, plastics, glazes, rubber, printed surfaces, many paper products, and even some foods. Only papers and textiles can be white without pigment. Virtually all this whiteness and lightness is supplied by titanium dioxide (TiO2) pigments. Void pigments make a minor contribution. The classic white pigments—lithopone, zinc sulfide, and the white leads—have essentially disappeared from commerce because TiO2 pigments perform much better, are much cheaper, and are nontoxic. Zinc oxide is still added to some paints as a mildewstat, but not for use as a white pigment. TiO2 pigments are manufactured by a major, globally distributed industry. Its products are sold for many applications; however, more than half of all white pigment goes into paints. In many coatings, white pigment is the single most expensive ingredient. To select the right pigment grade and use it well is an important challenge to the paint manufacturer. This chapter will familiarize coating manufacturers with white pigments and help them understand their options for selection, utilization, and testing. Toward this objective, I will first outline the commerce and manufacture of white pigments and then discuss their function, the substances that serve this function, and the commodities available. I will distinguish between product characteristics that describe the pigment itself and product performance, which are properties of paint films, that is, systems composed of pigment and binder.
Paper ID: MNL12199M
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