Organic and inorganic colour pigments matched to a physical standard and released on lightfastness, heat stability and migration — not on shade alone.
Fastness, heat stability and migration decide what chemistry is even eligible.
Organic pigments give clean, strong, brilliant shades but vary widely in heat resistance and can bleed in solvent or plasticiser. Inorganic pigments are duller and weaker but hold their shade through high processing temperatures and years of exposure. The service conditions of the article eliminate most of the palette before a colourist matches anything, and pretending otherwise produces a shade that passes on the drawdown and fails in the field.
6–8
Blue Wool lightfastness
The fastness range the specialty pigment classes are released against.
Matching is the third step, not the first.
Processing temperature, exposure, migration limits and regulatory restrictions are captured first. They define which chemistries remain eligible.
The colour is matched to the retained standard in the actual system, under the illuminants specified, and checked for metamerism against the alternates.
The candidate is put through heat, light and migration testing at the conditions the article will see, since a match that fails these is not a match.
The accepted shade is recorded with its tolerance, the standard is retained, and every subsequent batch is released against it rather than against the previous batch.
Chemistry is chosen against the service conditions, then against the shade.
Azo · phthalocyanine · quinacridone
Clean, strong, brilliant shades with high tinting strength, chosen where brightness matters and the processing window is known and moderate.
Oxides · mixed metal oxides
Opaque, extremely durable and thermally stable pigments for high processing temperatures, exterior exposure and long service lives.
To standard · ΔE released
Blends formulated against a supplied physical standard, released to an agreed colour difference and recorded so the shade is reproducible batch after batch.
No single number is sufficient on its own.
The measured deviation from the retained standard, and the figure a repeat order is actually released on.
Resistance to fading under daylight. It governs whether the article still looks specified after a year outdoors, and it is exposure-dependent.
The temperature the pigment holds its shade through, at a stated residence time. Exceeding it shifts the shade irreversibly during processing.
Whether the colour stays in the article or bleeds into what it touches. It governs use in plasticised systems and multi-layer construction.
How much pigment is needed to reach the shade. Released as a percentage of the standard so a formulation does not have to be re-costed each lot.
Reported against the applicable restriction list so the article can be certified without retesting the finished product.
Organic pigments give brighter, cleaner and stronger shades but vary in heat and migration resistance. Inorganic pigments are duller and weaker but far more stable thermally and outdoors. The processing temperature and the exposure usually decide before shade is considered.
It is when two samples match under one light source and differ under another. It is avoided by matching with the same pigment chemistry as the standard wherever possible, and by assessing the match under the specific illuminants named in the specification.
By releasing every batch against a retained physical standard to an agreed ΔE, never against the previous batch. Matching batch to batch allows a slow drift that is invisible each time and obvious after ten lots.
Exceeding the heat stability of the pigment for the residence time involved, or shear and reduction effects in the melt. A pigment rated at a temperature for a short residence may still shift in a slow line, so both figures are specified.
Yes, against a supplied physical standard and in the actual system. The tolerance, the illuminants and the fastness requirements are agreed first, and the accepted shade is then retained as the reference for all future production.
Send the physical standard, the processing conditions and the fastness the article needs, and we will come back with the chemistry, the loading and the tolerance.
