Specific Gravity: Specific gravity has been determined in an inert liquid at 20 C.
Oil Absorption: 10 gm. of pigment is placed on a glass plate and acid refind linseed oil is added from a burrette in drops, and the paste rubbed to get a spreadable paste. The quantity of oil required for 100 gms. of Pigment is then calculated and expressed as ml. oil/100 grams Pigment.
Light Fastness: The prints of the pigment dispersed in printing ink medium is exposed along with Standard Blue Scale and rating expressed in 1 to 8 scale. 8 denotes excellence and 1 denoting poor tastness.
Heat Resistance: A stoving paint of the Pigment is prepared in non yellowing medium and applied to a tin panel. The temperature upto which there is negligible change in the shade after stoving for 30 minutes is noted.
Fastness to solvents and chemicals: The test is carried out by placing 0.5 gms. of pigment in a folded paper, sealed at the top and suspended in 20 cc. of solvent in a stoppered test tube at room temperature for 24 hours. The staining noted and expressed in 1 to 5 scale.
In case of water, acid or alkali: 0.5 gm. of pigment is mixed with 10 ml. each & these liquids heated in a water bath for 10 mts. cooled and filtered. The filterate is assessed for colouration.
Soap bleeding: The test is carried out by placing completely dried draw-down/print on 20% Jelly made with neutral white Soap for 24 hours. Extent of bleeding noted and expressed in 1 to 5 scale.