Due to differences in users’ monitors, the colors presented are an approximation of the true color.
PB74-Cobalt Zinc Silicate Blue Phenacite
PB15:3-Phthalo Blue
PB74-Cobalt Zinc Silicate Blue Phenacite
inorganic
cobalt zinc silicate
(CoZi)2SiO4
Cobalt-zinc silicate is semi opaque and semi-soluble in water. It produces a warmer and darker blue that standard Cobalt Blue (PB28), and is used most often in glass and ceramics.
Cobalt-zinc silicate is extremely lightfast and temperature stable.
Cobalt-zinc silicate is toxic, and its toxictiy may be of greater concern that for Cobalt Blue (PB28) because it is semi-soluble in water.
Since the discovery of processes for mining Cobalt Blue (PB28) in the 19th century, additional processes for manufacturing and purifying other cobalt salts have become available. Their use as artist pigments has followed.
PB15:3-Phthalo Blue
organic
beta copper phthalocyanine
C32H16CuN8
Phthalo Blue PB15:3 is a structural variant of Phthalo Blue PB15 that produces more greenish tones.
Phthalo Blues are completely lightfast and stable and are permanent for all paint uses. They are currently used in inks, coatings, and many plastics due to their stability and are considered a standard pigment in printing ink and the packaging industry.
Phthalo Blues have no significant hazards, although those made before 1982 contained some PCBs (polychlorinated biphenyls).
Developed by chemists using the trade name Monastral Blue, the organic blue dyestuff now known as Phthalo Blue was presented as a pigment in November 1935 in London. Its discovery was accidental. The dark color was observed in a kettle where a dye was being made from a British dyestuff plant. The demand for such a pigment came from commercial printers who wanted a cyan to replace Prussian Blue.
UPC Code: 3167861690287