This Naphthol Red is an intense scarlet red pigment that is heavily staining. It has an average drying time. It is semi-transparent and has relatively poor covering power.
This Naphthol Red has been rated as having excellent lightfastness under ASTM testing, but other testing methods have demonstrated some tendancy for the color to fade with exposure to strong ultraviolet light. It has been considered a replacement for less lightfast naphthol reds such as PR3. Not suitable for exterior use.
Naphthol Reds are not considered toxic. Naphthol Red AS-D may cause eye, skin, or respiratory irritation. Contact with dry pigment should be avoided.
PY42-Yellow Iron Oxide
Fe2O3 • H2O
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.
Yellow Ochre has excellent permanence because ochres are some of the most permanent pigments available.
Yellow Ochre is non-toxic unless it contains manganese.
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.