Color Swatch created using heavy application/diluted application and was applied on cold press watercolor paper (150 lb) material.
This color contains the following pigments:
PB27—Antwerp Blue
Pigment Type
inorganic
Chemical Name
ferric ammonium ferrocyanide
Chemical Formula
C18Fe7N18
Properties
Antwerp Blue is a slightly warm and less saturated blue with good transparency and undertone clarity. It is a pale variety of Prussian Blue with 75% inert pigment. It has similar properties to pure Prussian Blue, but its overall performance is inferior.
Permanence
Antwerp Blue can fluctuate, fading in the light and recovering in the dark. In watercolor form, it fades when mixed with white pigment or extender. Although it has reasonably good lightfastness and permanence, it is not considered ideal for permanent painting.
Toxicity
Antwerp Blue is mildly toxic by ingestion, but is considered safe for external use. In the United States, ferric ferrocyanide is permitted as a coloring ingredient for externally applied cosmetics, but not for lipsticks or internal use. If the pigment is exposed to ultraviolet radiation, heated, or treated with acid, it becomes reactive and releases toxic hydrogen gas.
There has been some confusion and controversy about whether ferric ferrocyanide and ferric ammonium ferrocyanide should be classified as a "cyanide" and as a toxic or environmental pollutant. The United States Environmental Protection Agency has issued an administrative ruling that ferric ferrocyanide is not a toxic pollutant, and that its use as an ingredient in road salt and deicing mixes is permitted.
History
Antwerp Blue was developed through experimentation with Prussian Blue.
Alternate Names
Haarlem Blue, Mansa Blue, Mineral Blue
PG7—Phthalo Green
Pigment Type
organic
Chemical Name
polychlorinated copper(II) phthalocyanine
Chemical Formula
C32H3Cl13CuN8 to C32HCl15CuN8 or C32H16CuN8Cl15 (PG7) or C32Br6Cl10CuN8 (PG36)
Properties
Phthalo Green is a transparent, cool, bright, high intensity color used in oil and acrylics. It comes from a Phthalocyanine Blue pigment where most of the hydrogen atoms have been replaced with chlorine, forming highly stable molecules. It has similar pigment properties and permanence to Phthalo Blue. It is slow drying and an excellent base color for mixing a range of bright greens. Phthalo Green is considered a very good alternative to Viridian because it is intense and mixes well and can be used to emphasize mineral colors in various tints. However, its tinting strength is very high, so it can overpower other colors. This pigment most closely resembles the discontinued and toxic Verdigris.
Permanence
Phthalo Greens are completely lightfast and resistant to alkali, acids, solvents, heat, and ultraviolet radiation. 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.
Toxicity
Phthalo Green has no significant hazards, but it contained PCBs (polychlorinated biphenyls) until 1982.
History
This bright blue-green was developed in 1935 and has been in use since 1938.
Alternate Names
Bocour Green, Cyan Green, Intense Green, Monastral Green, Phthalocyanine Green, Rembrandt Green, Thalo Green, Winsor Green.