Pigment Specifications
Acid Resistance- Some pigments and dyes are degraded by
acids, and will have problems in exterior applications in areas
where there is an acid rain problem. As a test, a 5% aqueous
hydrochloric acid (HCl) solution is put on a painted panel for
30 minutes at room temperature, and then washed with cold water.
The results are evaluated visually for a change in color where
the acid was.
Alkali Resistance- Some pigments and dyes are degraded in
alkaline solution, and cannot be used in systems that inherently
have a pH greater than 7.0.
Bleed Resistance- Bleed is the migration out of the colorant
out of the system, with the most common example being, the fading of
a textile from repeated washings.
Oil Absorption- The weight of oil (in pounds) required to
wet 100 pounds of pigment.
Last Update- October 22, 1995- wld