Holbein Acryla Gouache Prussian Blue 20 ml

D105 Prussian Blue/Bleu de Prusse - Ultramarine [Blue] PB29 (inorganic, complex silicate of sodium and aluminum with sulphur), Phthalo Blue PB15 (organic copper Phthalocyanine), Titanium White PW6 (inorganic, Titanium dioxide)

Series: A

Lightfast: **

Pigment 1: Ultramarine [Blue] PB29

The name for this pigment comes from the Middle Latin ultra, meaning beyond, and mare, meaning sea because it was imported from Asia to Europe by sea. It is a prominent component of lapis lazuli and was used on Asian temples starting in the 6^th century. It was one of the most expensive pigments in 16^th century Europe, worth twice its weight in gold, and so was used sparingly and when commissions were larger. Ultramarine is currently imitated by a process invented in France in 1826 by Jean Baptiste Guimet, making blue affordable to artists and extending the range of colours on their palettes.

Series: A

Lightfast: ***

Pigment name: PB29-Ultramarine [Blue]

Pigment Type: Inorganic

Chemical Name: Complex silicate of sodium and aluminum with sulphur

Ultramarine is the standard warm blue, a brilliant blue pigment that has the most purple and least green in its undertone. It has a moderate to high tinting strength and beautiful transparency. Synthetic Ultramarine is not as vivid a blue as natural Ultramarine. Ultramarine dries slowly in oil and tends to produce clean, though granular, washes in watercolour. French Ultramarine mixes well with Alizarin colours in oil and watercolour to create a range of purples and violets. It can dull when mixed with white in acrylic form but mixes well with other colours. The shade varies based on the manufacturer. Considered a great colour for glazes, it is not suitable for frescoing.

Permanence: Ultramarine has excellent permanence, although synthetic Ultramarine is not as permanent as natural Ultramarine. It may discolour if exposed to acid because of its sulfuric content.

Toxicity: Ultramarine has no significant hazards.

Alternate Names: Ultramarine Hue, French Blue, French Ultramarine, Gmelin's Blue, Guimet's Blue, Permanent Blue, Royal Blue, Synthetic Ultramarine. New Blue describes particular shades of Ultramarine. Armenian Blue and Lazuline Blue are names for genuine Lapiz Ultramarine. Sky Blue is a pale tone of Ultramarine.

Pigment 2: Phthalo Blue PB15

Phthalocyanine Blues was developed by chemists using the trade name Monastral Blue. The organic blue dyestuff, now known as Phthalo Blue, was presented as a pigment in November 1935 in London. Its discovery was accidental. The dark colour was observed in a kettle where a dye was being made from a British dyestuff plant. The demand for such a pigment came from commercial printers who wanted cyan to replace Prussian Blue.

Pigments Name: PB15-Phthalo Blue

Pigment Type: organic

Chemical Name: copper phthalocyanine

Properties: Phthalo Blues are pure and clean primary blues with superior covering power. They have a very high tinting strength and tend to overwhelm other pigments, but if colour strength can be controlled, they make predictable mixed colours. In oil form, blues are intense and slow drying. When mixed with other colours or if chlorine is added, Phthalo Blue quickly tends towards green. When using alone, mix with some white, as Phthalo Blue can be semi-transparent and almost black on its own. It is among the most compatible of modern colours with mineral colours and is considered more reliable than Prussian Blue while sharing the same physical and colour properties. Phthalo Blue is a good colour for glazing.

Permanence: Phthalo Blues are completely lightfast and stable and are permanent for all paint uses. 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 Blues have no significant hazards, although those made before 1982 contained some PCBs (polychlorinated biphenyls).

Alternate Names: Bocour Blue, Cyan Blue, Helio Blue, Heliogen Blue, Intense Blue, Monastral Blue, Phthalocyanine Blue, Rembrandt Blue, Thalo Blue, Winsor Blue.

Pigment 3: 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.