Color Swatch created using heavy application/medium application/50% tint and was applied on acrylic primed canvas (7 oz) material.
This color contains the following pigments:
PY155—Bisacetoacetarylide Yellow 155
Pigment Type
organic, bisacetoacetarylide
Chemical Name
n/a
Chemical Formula
n/a
Properties
Pigment Yellow PY155 is a greenish yellow with high tinting strength and good solvent resistance. It is often used as a replacement for chromium yellow.
Permanence
Pigment Yellow PY155 has very good lightfastness, but some monoazo yellows have better weatherfastness. It may not be suitable for exterior applications. Grades with coarser particles have been reported to have much better weatherfastness.
Toxicity
n/a
History
Bisacetoacetarylide pigments are a subgroup of the disazo pigments. Although many have been described and patented, only a few are commercially available. Pigment Yellow PY155 is used in paints, plastics, printing inks, and industrial coatings.
Alternate Names
Novoperm Yellow 4G
PG17—Chromium Oxide Green
Pigment Type
inorganic
Chemical Name
chromium oxide
Chemical Formula
Cr2O3
Properties
Chromium Oxide Green is a dull, dense, willow or pale green color that is completely opaque. It has an average drying time and a low tinting strength. It is fairly flexible in oil form and is suitable for all purposes and mediums. This pigment is less versatile in mixtures than Viridian and Phthalocyanine Green, but mixes well with other colors without overpowering them.
Permanence
Chromium Oxide Green has excellent permanence, even at high temperatures.
Toxicity
Chromium Oxide Green is slightly toxic. Evidence of Chromium(III) carcinogenicity is inconclusive. Chromium(III) salts appear in greenish pigments such as PG17. Chromium(VI) salts, which appear in yellowish pigments, have been proven to cause cancer.
History
Louis-Nicolas Vauquelin discovered the element chromium in lead chromate in 1797. It began to be used as an enamel and ceramic color in 1809, but it had limited use as a pigment until 1862, because of its cost. It is the most commonly used green for military camouflage because it appears the same shade as living foliage under infrared light.
Alternate Names
Chrome Oxide Green, Olive Green, Permanent Green. Varieties of Chromium Oxide Green include Arnaudon's Green, Dingler's Green, Plessy's Green, and Schnitzer's Green.
PY42—Yellow Ochre
Pigment Type
n/a
Chemical Name
iron(III)-oxide, hydrated
Chemical Formula
Fe2O3 • H2O
Properties
Yellow Ochre provides artists with earthtones from cream to brown. It has good hiding power, produces a quick drying paint, and can be safely mixed with other pigments. Its transparency varies widely from opaque shades to more transparent ones, which are valued for their use as glazes. If gypsum is present, Yellow Ochre is not suitable for frescoing. (See Brown Ochre, PY43.) PY42 is made from synthetic iron oxides. PY43 is made from natural iron oxide.
Permanence
Yellow Ochre has excellent permanence because ochres are some of the most permanent pigments available.
Toxicity
Yellow Ochre is non-toxic unless it contains manganese.
History
Ochre comes from the Greek word ochros, meaning pale yellow. It was one of the first pigments to be used by human beings, and evidence of its use has been found at 300,000 year old sites in France and the former Czechoslovakia.
Alternate Names
Chamois, Iron Yellow, Mars Orange, Mars Yellow, Minette, Ochre, Sil, Yellow Earth, Yellow Oxide. Varieties of Yellow Ochre include Brown Ochre, Flesh Ochre, Roman Ochre, Spruce Ochre, and Transparent Gold Ochre.
