Colored pigments are categorised as either organic or inorganic.
Each have distinct characteristics which, in the past, were used to distinguish one from
the other. For example, organic pigments are traditionally transparent. However,
modern manufacturing techniques are capable of imparting properties not previously
associated with the chemical type: it is now possible to produce high opacity organic pigments.
The use of inorganic pigments dates back to the early cave paintings
that are 30,000 years old. Although they occur naturally, for the manufacturing of paint
they usually require modification. All white pigments are inorganic as are a wide range of
colored pigments.
Organic pigments are relatively new. Although natural dyes have been
precipitated on to inorganic bases (known as lakes) and used in artists' colors since the
middle ages (e.g. madder lake and crimson lake), true organic pigments have only
been known since the early years of the twentieth century. They divide in two
sub-groups: one of vegetable and the other of animal origin.
The properties that have traditionally been associated with inorganic and organic
pigments are summarized in the table below.
Compared Pigments Properties
Pigment properties
Inorganics
Organics
Classical
with High
Performances
Color, Purity
Often dull
Usually bright
Opacity
High
More or less transparent
Color strength
Middle to Low
Normally High
Light Fastness
(Blue scale)
Good to High (7-8)
Low to Middle (< 7)
Good to High (7-8)
Weather Resistance
Varies (depending on chemistry)
Insufficient
Middle to High
Heat resistance
In general > 500 °C
Rarely < 200 ° C
150 to 220 ° C
200 to 300 ° C
Fastness to solvents -
Bleed resistance
High
Middle to Good
Good to High
Resistance to chemicals
Varies (depending on chemistry)
High (except for salts)
High
Price
Low to Middle
Middle
High
In this section, we have selected for you the main families of pigments. You will find all the product, physical, structural and use information needed:
