D116 Light Magenta/Magenta Clair - Naphthol Red PR170 (organic, Naphthol AS), Titanium White PW6 (inorganic, Titanium dioxide)

Series: A

Lightfast: **

Pigment 1: Naphthol Red PR170

Naphthol pigments are dyes that are "laked" to form pigments. First developed by the German chemical company Hoechst A.G. before World War I, artist paints began in the 1920s. Pigment Red PR170 is a Naphthol AS pigment, chemically related to the diarylide yellow pigments. The Naphthol AS pigments comprises a range of reds. They are used in plastics, textiles, and printing inks.

Pigment Name: Naphthol Red PR170

Pigment Type: organic, Naphthol AS

Chemical Name: n/a

Properties: Pigment PR170 is a bright deep red with bluish undertones. It has an average drying time. It has two crystalline forms that differ significantly in opacity. The more transparent form (F5RK) tends to be more bluish and is less lightfast.

Permanence: The lightfastness and weather fastness of Pigment PR170 varies, depending on the application and the crystalline form. The opaque state (F3RK) has excellent lightfastness and is more weather resistant. The transparent form (F5RK) has lightfastness considered acceptable in pure applications, but it fades more in tints. Neither state is deemed to be suitable for exterior use.

Toxicity: Naphthol Reds are not considered toxic. They may cause eye, skin, or respiratory irritation. Should avoid contact with dry pigment.

Alternate Names: Naphthal, Naphthol Bordeaux, Naphthol Carbamide, Naphthol Carmine, Permanent Carmine, Naphthol Crimson, Permanent Red, Permanent Red F3RK (more opaque), Permanent Red F5RK (more transparent).

Pigment 2: Titanium White PW6

Titanium is the ninth most abundant element in the Earth's crust; however, mineral deposits that are economical to mine are less common. Titanium dioxide was first discovered in 1821, although it could not be mass-produced until 1919. Widespread use of the pigment began in the 1940s. Since that time, it has become the most commonly used white pigment. The name comes from the Latin word Titan, the name for the elder brother of Kronos and ancestor of the Titans, and the Greek word tito, meaning day or sun.

Pigment Name: Titanium White PW6

Pigment Type: Inorganic

Chemical Name: Titanium dioxide

Properties: Titanium White is the most brilliant of the white pigments. It is considered an all-purpose oil colour useful in all techniques and the best all-around white. Its masstone is neither warm nor cool, placing it somewhere between Lead White and Zinc White. It is less prone to cracking and yellowing than Lead White, but it still yellows easily. Titanium White dries slowly in oil form, more slowly than Lead White but more quickly than Zinc White. It is opaque in oil and acrylic forms and semi-opaque in watercolour. This pigment has good chemical stability, and its tinting strength is superior to both Lead White and Zinc White.

Permanence: Titanium White has excellent permanence and lightfastness.

Toxicity: Titanium dioxide is highly stable and is regarded as completely non-toxic. Animal studies do not indicate that it is absorbed biologically, even after long periods of exposure. The primary safety concern is with inhalation of fine pigment dust particles. If inhaled in large amounts over the course of several years, Titanium White may cause a benign pneumoconiosis that is visible on x-rays. The National Institute of Occupational Safety and Health (NIOSH) considers fine titanium dioxide particles, if inhaled, to be a human carcinogen. The primary concern for artists is to avoid exposure to fine particulate dust from raw pigments.

Alternate Names: None.