ISO 23900-3:2015 specifies a method of determining in polyethylene (PE) the colouristic properties of a test pigment relative to a standard, and the ease of dispersion DHPE of pigments from the differences in colour strength on dispersing colouring materials under various conditions.
Method A is appropriate for use with organic powder pigments and carbon black pigments in powder form, many of which are subject to compaction (reagglomeration under pressure), for inorganic pigments in powder form and for pigment preparations in powder or flake form.
Method B is appropriate for testing pigments and pigment preparations in granular form and for inorganic pigments in any form.