Holbein Artists' Gouache - Pink, 15 ml tube

Pigment Information

This color contains the following pigments:

BV10-Rhodamine B

PW6-Titanium White

Pigment Name

BV10-Rhodamine B

Pigment Type

organic, fluorone dye

Chemical Name

Rhodamine B

Chemical Formula

C28H31N2O3Cl

Properties

Rhodamine B is a staining violet dye that has fluorescent properties. It is extremely soluble in both water and alcohol. In art materials it is laked as a pigment.

Permanence

Rhodamine B, like all fluorescent dyes, is not considered to be lightfast. It is recommended for permanent works of art only if they can be adequately protected from exposure to ultraviolet light.

Toxicity

The fluorescent dye Rhodamine B is toxic, and its use is banned in food, textiles, and cosmetics. It is harmful if swallowed, inhaled, or absorbed through the skin. It has been shown to be carcinogenic in rats when injected subcutaneously, producing local

History

Rhodamine B, discovered in 1887, is used as a staining fluorescent dye in the biological sciences, for microscopy. It is also used as a laser dye. Because of its low cost, high tinting strength, solubility in water and alcohol, and relative stability for a fluorescent, it has sometimes been used as a food colorant, even though its use in food and cosmetics has been banned in most countries for many years. There have been several highly publicized recalls of food and cosmetic products contaminated with Rhodamine B.

Pigment Name

PW6-Titanium White

Pigment Type

inorganic

Chemical Name

titanium dioxide

Chemical Formula

TiO2

Properties

Titanium White is the most brilliant of the white pigments. It is considered an all purpose oil color 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 watercolor form. 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 non-toxic.

History

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 from the Greek word tito, meaning day or sun.