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Encaustic is a wax based paint (composed of beeswax,
resin and pigment), that is kept molten on a heated palette. It is
applied to a porous surface and then reheated in order to fuse the
paint. The word ‘encaustic’ has no connection to the word caustic; it
comes from the Greek word enkaiein, meaning to burn in, referring to the
process of fusing the paint.
Encaustic is perhaps the most beautiful of all artists' paints, and it
is as versatile as any 21st century medium. It can be polished to a high
gloss, carved, scraped, layered, collaged, dipped, cast, modeled,
sculpted, textured, and combined with oil. It cools immediately, so that
there is no drying time, yet it can always be reworked.
Encaustic is also the most durable artists' paint. This is due to the
fact that beeswax is impervious to moisture. Because of this, it will
not deteriorate, it will not yellow, and it will not darken. Encaustic
paintings do not have to be varnished or protected by glass.
Encaustic paint does not require the use of solvents. As a result, a
number of health hazards are reduced or eliminated.
Encaustic is a beeswax-based painting medium that is worked with heat.
It can be used as a luminous traditional painting medium, but it also
has the potential to obscure the boundaries between mediums like no
other art material, resulting in works that are just as much about
painting or sculpture as they are about photography, drawing,
printmaking, installation or a variety of craft techniques. Artists of
all kinds are discovering its unifying potential, unique properties and
versatility.
Painting with encaustic is a multi-step process. First, the paint must
be melted, or liquefied. Next, the molten paint is applied to a porous
surface. Then the applied wax is reheated, or fused into, the working
surface, allowing it to form a good bond. As a final option, the cooled
paint can be buffed to bring up the luster of the wax and resin.
Beeswax (general)
Beeswax is a natural animal wax secreted by bees and used to create the
honeycombs of the hive. The natural color of beeswax when it is secreted
is white. (See beeswax unrefined.)
Beeswax is the classic component of encaustic paint and all other wax
related arts from ancient times. Its great versatility as an art
material derives from its stability as a solid at normal temperatures
and its fluidity at relatively low heated temperatures, its resistance
to moisture, its ability to be polished, the range of possible surface
textures, its adhesiveness, its ability to transparentize, and its
plastic structural properties that allow it to be cast, carved, molded,
roughened, incised, and scraped.
Beeswax (unrefined)
Most of the harvested beeswax is colored in a range of earthy hues from
yellow to black. The coloration is caused by pollen and propolis (see
definition). The higher up in the hive the wax is, the less it will be
colored. The caps that cover the cells of the hive are usually white.
Other impurities include dirt and body parts from the bees.
Propolis is a resinous substance collected from plants by the bees and
secreted from the thorax of the bee when constructing the hive. Its
purpose is to cement together the wax of the hive. For this reason, it
is known as “bee glue.”
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Bleached beeswax
Beeswax varies in its ability to be refined depending on strain of bees,
the vegetation from which the bee derived its pollen, weather-related
stress on the bee (which affects the amount of propolis in the wax), the
age of the wax in the hive, etc. These conditions make some waxes unable
to be refined (or bleached) to a white color. These are sold as refined
yellow waxes.
The industrial bleaching of beeswax is done in one of three ways:
1.chemical bleaching, using peroxide or sulfuric acid: Chemical
bleaching can be harsh on the wax, creating free fatty acids and making
the wax more reactive to pigments and pollutants. Chemical bleaching can
whiten colorants that other bleaching processes can’t, but these
colorants can later return to their original color.
2.sun bleaching, in which the wax is exposed to the sun, which bleaches
out the colorants: Sun bleaching is a gentle and effective method of
bleaching. Sun-bleached wax is usually softer. But the process is
expensive and requires a great deal of space.
3.Filtration, in which the wax is forced through a series of paper
filters containing activated carbon. Filter bleaching is accomplished by
filtering the wax through a mixture of activated carbon and clay that
absorb the colorants. The wax is then run under pressure through a
series of paper filters that take out all foreign matter.
Of these three, filtration is preferrable.
Bleached beeswax
Beeswax varies in its ability to be refined depending on strain of bees,
the vegetation from which the bee derived its pollen, weather-related
stress on the bee (which affects the amount of propolis in the wax), the
age of the wax in the hive, etc. These conditions make some waxes unable
to be refined (or bleached) to a white color. These are sold as refined
yellow waxes.
The industrial bleaching of beeswax is done in one of three ways:
1.chemical bleaching, using peroxide or sulfuric acid: Chemical
bleaching can be harsh on the wax, creating free fatty acids and making
the wax more reactive to pigments and pollutants. Chemical bleaching can
whiten colorants that other bleaching processes can’t, but these
colorants can later return to their original color.
2.sun bleaching, in which the wax is exposed to the sun, which bleaches
out the colorants: Sun bleaching is a gentle and effective method of
bleaching. Sun-bleached wax is usually softer. But the process is
expensive and requires a great deal of space.
3.Filtration, in which the wax is forced through a series of paper
filters containing activated carbon. Filter bleaching is accomplished by
filtering the wax through a mixture of activated carbon and clay that
absorb the colorants. The wax is then run under pressure through a
series of paper filters that take out all foreign matter.
Of these three, filtration is preferrable.
Pharmaceutical grade beeswax
Pharmeceutical grade beeswax is a standard set by the government that
certifies that the wax meets certain chemical requirements and that it
is pure beeswax, unadulterated with other waxes (such as paraffin or
microcrystalline), rosins, etc. The chemical standards are mainly of
importance to the cosmetic and pharmaceutical use of beeswax. For the
artist, the main importance is the physical standard that the wax is
unadulterated.
Wax
Wax is a plastic material that comes from many sources:
•Animal: beeswax
•Vegetable: carnauba, candelilla
•Petroleum: paraffin, microcrystalline
•Mineral: montan, ozokerite
Chemically animal and vegetable waxes have similar properties to animal
and vegetable oils. The waxes differ from the oil mainly in their
physical characteristics in that they are solid at normal temperatures
while the oils are fluid. As a result, they do not have a drying time
but change from fluid to solid in very short time to temperature.
Unlike animal and vegetable waxes, petroleum waxes are chemically inert
and less reactive. Their drawbacks are that they will oxidize and yellow
over time if exposed to the air. Paraffin is a very brittle wax that
makes it problematic when used for encaustic.
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