Gamblin 1980 Oils - PB28 Cobalt Blue; PB15:2 Phthalo Blue
Gamblin’s approach is different. 1980 colours contain pure
pigments, the finest refined linseed oil, and marble dust (calcium carbonate).
Since oil painting began, these three ingredients have made more affordable colours.
Painters experience true colours without homogenized texture
or muddy colour mixtures. Gamblin's approach to using traditional raw materials and processes ensures that artists experience the luscious working properties they expect from their oil colours.
Cobalt Blue is considered a “True blue,” first manufactured
in 1804. This colour is well worth the price because of its functional
properties and unique colour, which cannot be mixed.
PIGMENT COMPOSITION AND PERMANENCE
- Pigment Name: PB15:1 Phthalo Blue (Cobalt (II) oxide +
aluminum oxide)
- Pigment Type: Organic
PROPERTIES
Phthalo Blue PB15:1 is a structural variant of Phthalo Blue
PB15 that produces more reddish tones.
PERMANENCE
Phthalo Blues are lightfast, stable, and permanent for all
paint uses. Due to their stability, they are currently used in inks, coatings,
and many plastics 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).
HISTORY
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
made from a British dyestuff plant. The demand for such a pigment came from
commercial printers who wanted a cyan to replace Prussian Blue.
PIGMENT COMPOSITION AND PERMANENCE
- Pigment Name: PB28 Cobalt Blue (Copper phthalocyanine)
- Pigment Type: inorganic
PROPERTIES
Cobalt blue is a semitransparent pigment with low to
moderate tinting strength. When it dries, it appears lighter and less
saturated. Pigment particles are large and grainy. Differences in how the
pigment is ground and mixed lead to considerable differences in performance
among various manufacturers.
PERMANENCE
Cobalt blue is absolutely lightfast and extraordinarily
stable. Cobalt salts' high temperature stability makes them the standard for
blues used in ceramics and glassware.
TOXICITY
Cobalt salts are toxic. Avoid respiratory and skin contact.
Soluble cobalt may cause irritation and allergic reactions through contact with
the skin. It is considered a possible carcinogen.
HISTORY
Since ancient times, smalt blue has been used to colour
glass and ceramics. Cobalt salts, which give smalt its characteristic blue
colour, were identified in the 18th century. Techniques for manufacturing
Cobalt Blue, a chemically pure salt of cobalt and aluminum oxide, were
developed in 1802.
