Term: Pigment
**Economic Impact of Pigments:**
– Around 7.4 million tons of pigments were marketed worldwide in 2006.
– The global pigment industry is valued at $30 billion.
– Titanium dioxide, used for white brightness enhancement, is valued at $13.2 billion annually.
– Ferrari red pigment is valued at $300 million yearly.
**Historical Significance of Pigments:**
– Minerals have been used as colorants since prehistoric times.
– Lapis lazuli was a favored blue pigment.
– Charcoal has been used as a black pigment since ancient times.
– Egyptian blue was the first known synthetic pigment.
– Synthetic pigments like vermilion and Indian yellow have historical significance.
**Manufacturing and Standards in Pigment Industry:**
– Before synthetic pigments, color consistency was a challenge.
– The Munsell color system describes color in three dimensions.
– Standardized methods for pigment chemistry were established in the mid-20th century.
– The International Organization for Standardization (ISO) develops technical standards for pigments.
– ISO standards cover general methods of testing pigments and specific categories like ultramarine and titanium dioxide.
**Chemical Composition and Properties of Pigments:**
– Pigments absorb specific wavelengths of light.
– The bonding properties of pigments determine their color.
– Pigments reflect or scatter light of other wavelengths.
– Appearance of pigments depends on the light source.
– Substances like binders and fillers can affect the color of pigments.
– Factors like lightfastness, heat stability, toxicity, tinting strength, and staining are crucial properties of pigments.
**Color Communication and Swatches:**
– Swatches are used to communicate colors accurately in various media.
– Printed swatches like PANTONE, RAL, and Munsell are widely used standards for color communication.
– Plastic swatches offer special effects like pearl, metallic, and fluorescent for plastics.
– Computer swatches face challenges in replicating pigment appearance accurately.
– Biological pigments in plant or animal cells serve various biological purposes and differ from structural color.
A pigment is a powder used to add color or change visual appearance. Pigments are completely or nearly insoluble and chemically unreactive in water or another medium; in contrast, dyes are colored substances which are soluble or go into solution at some stage in their use. Dyes are often organic compounds whereas pigments are often inorganic. Pigments of prehistoric and historic value include ochre, charcoal, and lapis lazuli.
