Gamblin 1980 Oil - PG7 Phthalo Green; PG18 Viridian
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.
Viridian was first synthesized in 1859; nontoxic Viridian
replaced Verdigris and Emerald Green as a glazing colour by the turn of the
20th century. It has good tinting strength, and its tint is muted like the
colours of the natural world.
PIGMENT COMPOSITION AND PERMANENCE
- Pigment Name: PG7 Phthalo Green (Polychlorinated copper(II)
phthalocyanine)
- Pigment Type: Organic
PROPERTIES
Phthalo Green is a transparent, cool, bright, high-intensity
colour used in oil and acrylics. It comes from a Phthalocyanine Blue pigment in
which most hydrogen atoms have been replaced with chlorine, forming highly
stable molecules. It has pigment properties and permanence similar to Phthalo
Blue.
It is slow drying and an excellent base colour for mixing a
range of bright greens.
Phthalo Green is considered an excellent alternative to
Viridian because it is intense, mixes well, and can be used to emphasize
mineral colours in various tints. However, its tinting strength is very high,
so that it can overpower other colours. This pigment most closely resembles the
discontinued and toxic Verdigris.
PERMANENCE
Phthalo Greens are completely lightfast and resistant to
alkali, acids, solvents, heat, and ultraviolet radiation. 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 Green has no significant hazards but contained PCBs
(polychlorinated biphenyls) until 1982.
HISTORY
This bright blue-green was developed in 1935 and has been
used since 1938.
PIGMENT COMPOSITION AND PERMANENCE
- Pigment Name: PG18 Viridian (Hydrated chromium (III)-oxide
dehydrate)
- Pigment Type: inorganic
PROPERTIES
Viridian is the standard green. It is stable, robust, and
cold, with an emerald green undertone. It has a transparent hue, good tinting
strength, a dark masstone that can be almost black at full power, and a slow
drying time in oil form.
Viridian is commonly replaced by the darker, more saturated,
and staining Phthalo Greens, but its properties make it a necessary part of the
palette of an experienced landscape painter.
PERMANENCE
Viridian has excellent permanence, except in
high-temperature work, and is highly valued as a glazing colour.
TOXICITY
Viridian is slightly toxic.
HISTORY
Viridian's name comes from the Latin viridis, meaning green.
Guignet patented the process for manufacturing Viridian, or Transparent Oxide
of Chromium, in Paris in 1859. However, it was discovered by Pannetier and
Binet in 1838. Viridian replaced Verdigris, which was reactive and unstable,
and Emerald Green, a poisonous copper aceto-arsenite used as rat poison in the
sewers of Paris.
