1.
About pigments.
Pigments
are the dusty particle-materials which make up our painting colours.
They are insoluble in liquids, but mixed in combination with a binder
(oils, resins, waxes, egg-yolk, acryl, etc.) or other vehicles they are
the ready colours to paint with.
In pre-historic
times, about 15.000 B.C. the 'artists' used charred bones or wood to get
black colour, chalk deposites to get white colour. Red and yellow
colourants had been used from minerals found in the soil or clay. About
8.000 B.C. the Egyptian 'artists' discovered the processing of natural
minerals, animal products and vegetable matter into useful colours.
Modern colours have
a short history. They have been developed in about 1860, when many
colours are derived from 'coal-tar' which belongs to the chemical family
of the 'synthetic organics'. The fugitiv nature of this colours got them
a bad reputation. Further development found in about 1870 the synthetic
duplication of the natural colourants.
In the 1930's and 1930's most of the colours have passed an improvement
in terms of colour range and durability. Processed minerals and
synthetic organic pigments have been copied by synthesized processes in
laboratories under controlled conditions.
Our today's artist's colours are mainly of synthetic organic nature and
are extensively tested for lightfastness and to be permanent.
If you are buying
painting colour today from serious colour manufacturers you will find on
the labels the name of the colour and its composition ingredients. Also
you will find the rational nomenclature indications and health label. If
there is no description from which origin the colour is made you should
be suspicious about the components used in this colour. In most of the
cases cheap pigment substitutes are used.
To understand in full about the difference in colour qualitities, please
read further on this article about the pigments.
2.
A word about
toxic pigments.
It is for
your own protection to notice the following:
when you are
dealing with pigments,
always take extra care and precaution.
The dry pigment
powders can present a health hazard, because toxic substances can enter
your body through the skin and mouth, or by inhaling the powders.
A proper protection and extra care is strongly advised when you are
dealing with these powders .
Some of the pigments are
highly toxic, too.
Some of
the pigments which are used in early years of paint-making are highly
toxic. They are replaced by today's substances, which are not that much
dangerous anymore. (In some cases the brilliance of the colour
appearance is gone, by changing the original pigments into substitute
substances.) It is also a care advise to read always the health lables
on the packages (and of cause on the colour tubes).
If you are wearing
rubber gloves and a mask (covering mouth and nose), the risks are
minimised. If you want to take a portion of extra care you can wear
splash goggles, too.
Because of the
dusty nature of pigments, avoid to splash dry pigments around so that
dust hangs in the air, and also avoid overexposure to the dust. Once the
pigments are dispersed in the binder or medium their hazards are
considerably reduced.
Always store your
pigments in covered containers. Lable them clearly including the health
hazards and promptly replace the covers after use.
After cleaning up
the working space, where you used pigments, wash the used tools and your
hands thoroughly in warm soapy water.
3. Requirements for a
paint pigment:
1. Should be a smooth, finely divided powder.
2. Should be insoluble in the medium in which it is used.
3. Should withstand the action of sunlight without changing
colour, under conditions to which the painting might
normally be exposed.
4. Should not exert a harmful chemical action upon the
medium or upon other pigments with which it is to
be mixed.
5. Should be chemically inert and unaffected by materials
with which it is to be mixed or by the atmosphere.
6. Should have the proper degree of opacity or transparency
to suit the purpose for which it is intended.
7. Should be of full strength and contain no added inert
or loading ingredients.
8. Should conform to accepted standards of colour and
colour quality and exhibit all the desirable
characteristics
of its type.
9. Should be purchased from a reliable house that understands
and tests its colours, selects them from worldwide
sources,
and can furnish information as to origin, details of
quality, etc.
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