Organic Pigments for Plastics: 12 Chemical Classes, Properties and Selection

Organic pigments for plastics are insoluble, carbon-based colorants, from monoazo yellows and azo lakes to phthalocyanine blues and diketopyrrolopyrrole reds, that colour a polymer as dispersed particles at typically about 2 wt% and give the transparent, deep shades that inorganic pigments cannot reach. They split into 12 chemical classes that behave very differently in the melt, so which class survives which polymer, and which one distorts a moulded part?

Colorants are a small share of the additive load by weight but a large share of its chemistry. Colorants account for 2 % of all plastic additives by weight, and pigments make up 127 of the 418 substances in ECHA's plastic additives mapping, the largest single function group. Organic pigments carry much of that chemistry: about 250,000 t of organic pigment were produced in 2006, about a quarter of it diarylide yellows.

This page defines an organic pigment, explains how chromophore, crystal form and dispersion set its colour, and walks through the 12 classes, the azo and polycyclic groups, the comparison with inorganic pigments, the 5 deciding properties, selection by polymer, loading, testing, regulation, producers and the complete list of 44 organic pigments. The hub on colorants for plastics places organic pigments beside the other 8 colorant types, from titanium dioxide to optical brighteners.

Key figures:

• 12 chemical classes: 6 azo classes and 6 polycyclic classes
• 44 organic pigments profiled with a substance page, each with C.I. name, CAS number and EU registration band
• About 2 wt%: the typical organic pigment concentration in the compound in ECHA's plastic additives mapping
• About 200 °C: the onset above which diarylide yellows decompose into monoazo species (Science Advances, 2025)
• +13.6 to +22.3 %: flow-direction shrinkage increase in polypropylene with 1 to 5 wt% of a phthalocyanine masterbatch (International Journal of Molecular Sciences, 2023)

What Is an Organic Pigment?#

An organic pigment is a colorant whose colour comes from a carbon-based chromophore, such as an azo group or a fused-ring system like phthalocyanine, and which stays insoluble in the polymer, so it colours as a dispersed particle rather than as a dissolved molecule. That insolubility is what separates it from a solvent dye of the same chemistry, and the crystal form and particle size decide its shade as much as the molecule does. Its performance in a part therefore depends on particle size, crystal form and dispersion quality, not on chemistry alone. US food-contact law uses the wider term: 21 CFR 178.3297(a) defines a colorant as a dye, pigment or other substance used to impart colour to, or alter the colour of, a food-contact material.

What makes a pigment "organic"?#

A pigment is organic when its colour comes from a carbon-based molecule, so a copper phthalocyanine blue or a calcium azo lake is an organic pigment even though the molecule contains a metal atom. Inorganic pigments are a different chemistry: metal oxides, sulfides and aluminosilicates, such as titanium dioxide, iron oxides and ultramarine. The deciding feature is the chromophore, not the element list, and 4 kinds of organic pigment carry a metal atom and remain organic pigments, as listed below.

• Copper phthalocyanines: PB15, PG7 and PG36, with copper at the centre of the macrocycle (PB15: C32H16CuN8)
• Calcium lakes: PR48:2, PR57:1, PY168 and PY183, calcium salts of azo pigments (PR57:1: C18H12CaN2O6S)
• Barium lakes: PR53:1, the barium salt of an azo pigment (C34H24BaCl2N4O8S2)
• Nickel complexes: PY150, a nickel azobarbiturate complexed with melamine, with no single formula

The metal still matters for compliance: it is the copper, barium or nickel that the EU Annex II migration limits measure, not the organic chromophore.

Organic pigment or solvent dye: why insolubility decides#

The same chromophore family can give a pigment or a dye: quinophthalone is the insoluble pigment PY138 and also the polymer-soluble Solvent Yellow 114, so what makes an organic pigment is its insolubility in the polymer, not its chemistry. Anthraquinone shows the same split, as the red pigment PR177 and as the solvent dyes Solvent Violet 13 and Solvent Blue 97. The table below compares the 3 chemistry families that appear on both sides of the line in our database.

A dissolved dye gives full transparency but stays mobile: solvent dyes suit predominantly amorphous thermoplastics, such as polystyrene, SAN, ABS, PMMA, polycarbonate and PET, and migrate in polyolefins. Transparent colours in polystyrene, polycarbonate and PMMA are made with solvent dyes for plastics, which dissolve instead of scattering.

How Do Organic Pigments Colour a Plastic?#

Organic pigments colour a plastic by absorbing part of the visible spectrum while scattering little light, because their refractive index sits close to the polymer's, and they reach their full colour strength only once their agglomerates are broken down in the melt. Titanium dioxide works the opposite way, hiding through its high refractive index and an optimal crystal size of about 220 nm. Why, then, does the same molecule give different shades from different suppliers?

Chromophore, crystal form and dispersion#

An organic pigment's colour is set by 3 variables: the chromophore that absorbs the light, the crystal form in which the molecules pack, and the size and dispersion of the particles in the polymer. The chromophore is the light-absorbing part of the molecule: an azo (hydrazone) group in PY83, the conjugated copper phthalocyanine macrocycle in PB15, and the diketopyrrolopyrrole core of PR254, whose molecules are held together by strong intermolecular hydrogen bonding. Chlorinating the phthalocyanine ring shifts its absorption from blue to green, which is how the chemistry of PB15 becomes PG7.

Crystal form changes both shade and stability. Copper phthalocyanine is sold in alpha forms (PB15, 15:1, 15:2) and in the more stable beta forms (15:3, 15:4), and quinacridone PV19 is a strong red as the gamma polymorph and a maroon with better weathering as the beta polymorph.

Dispersion decides how much of that colour reaches the part. Pigment particles arrive as agglomerates, and only wetted, broken-down particles give full colour strength and a low filter pressure value. Waxes and other dispersing agents for plastics and masterbatch wet the pigment surface, lower melt viscosity and stop the particles re-agglomerating.

Why organic pigments are transparent and strong#

Organic pigments stay transparent in a polymer because their refractive index is close to the polymer's, so they add colour without hiding what lies behind it, and they do so at lower loadings than opaque pigments: mostly about 2 wt% in ECHA's mapping, against 5 wt% for titanium dioxide and complex inorganic pigments. Tinting strength, the colour delivered per unit of pigment, is the second half of that advantage.

Transparency shows up in the same resin at the same dose. In a 2023 polypropylene study in the International Journal of Molecular Sciences, a phthalocyanine green masterbatch kept the moulded parts transparent while a chromium and copper oxide green, dosed over the same 1 to 5 wt% range, made them opaque. Strength changes the price comparison: a grade with twice the tinting strength at twice the price per kilogram is cost-neutral, so organic pigment grades are compared by cost-in-use at equal colour.

What Are the 12 Classes of Organic Pigments Used in Plastics?#

The 12 classes of organic pigments used in plastics are monoazo pigments, azo lakes, diarylide yellows, disazo condensation pigments, benzimidazolones, metal-complex azo pigments, phthalocyanines, quinacridones, diketopyrrolopyrroles (DPP), perylenes, isoindoline and quinophthalone yellows, and the dioxazine, anthraquinone and indanthrone pigments. The first 6 are azo pigments, built on one or two azo groups, and the last 6 are polycyclic pigments, built on fused ring systems; between them they cover every hue from greenish yellow to blue and green. This reference groups its 44 organic pigments into these 12 classes, an editorial grouping that keeps the naphthol AS reds with the monoazo pigments and the quinophthalones with the isoindolines. Table T1 lists the 12 classes with the pigments profiled in each.

Table T1. The 12 classes of organic pigments used in plastics.

Registration bands are EU REACH tonnage bands from ECHA CHEM (checked 22 September 2026). FDA limits are legal maxima for food contact under 21 CFR 178.3297, not dosages.

Each pigment is identified by its C.I. Generic Name and its CAS number, and the Colour Index lists over 27,000 products under about 13,000 C.I. Generic Names. How the names and the Constitution Numbers are built is explained under Colour Index (C.I.) pigment names.

1. Monoazo pigments: PY74, PR170 and PO67#

Monoazo pigments carry a single azo group, and the 3 profiled for plastics are the monoazo yellow C.I. Pigment Yellow 74 (PY74, CAS 6358-31-2), the naphthol AS red C.I. Pigment Red 170 (PR170, CAS 2786-76-7) and the pyrazoloquinazolone orange C.I. Pigment Orange 67 (PO67, CAS 74336-59-7). PY74 (C.I. 11741) and PR170 are each registered in the EU at 1,000 to 10,000 t a year, and PO67 (C.I. 12915) at 100 to 1,000 t a year.

PY74 is the transparent monoazo yellow of the class, which ECHA's mapping records at 2 wt% in polyolefins, PVC, ABS, PET, polycarbonate and polystyrene, a record of where it is found rather than a heat rating. The transparent yellow of the class is profiled on Pigment Yellow 74 (monoazo yellow).

2. Azo lakes: PR48:2, PR53:1, PR57:1, PY168 and PY183#

Azo lakes are azo pigments precipitated as calcium or barium salts, and the 5 profiled for plastics are C.I. Pigment Red 48:2 (PR48:2, CAS 7023-61-2), Pigment Red 53:1 (PR53:1, CAS 5160-02-1), Pigment Red 57:1 (PR57:1, CAS 5281-04-9), Pigment Yellow 168 (PY168, CAS 71832-85-4) and Pigment Yellow 183 (PY183, CAS 65212-77-3). Lithol Rubine BK (PR57:1, C.I. 15850:1) is the calcium lake of a BONA (3-hydroxy-2-naphthoic acid) azo pigment, and its EU registration band of 10,000 to 100,000 t a year is the highest of the 44 organic pigments profiled here, shared only with phthalocyanine blue.

The metal in a lake counts in food contact. PR53:1 (Lake Red C) is a barium lake, and barium carries an EU migration limit of 1 mg/kg of food under Annex II of Regulation (EU) No 10/2011. The highest-tonnage lake, profiled on Pigment Red 57:1 (Lithol Rubine BK), is not listed in 21 CFR 178.3297 (eCFR current to 18 September 2026).

3. Diarylide yellows and pyrazolone orange: PY12, PY13, PY14, PY17, PY83 and PO13#

Diarylide yellows are disazo pigments built on 3,3'-dichlorobenzidine, and the 5 profiled for plastics (C.I. Pigment Yellow 12, 13, 14, 17 and 83), together with the pyrazolone orange PO13, share one hard limit: above about 200 °C they decompose into monoazo species and can release 3,3'-dichlorobenzidine. A 2025 study in Science Advances on solvent-recycled polyethylene placed the first thermogravimetric decomposition peak of diarylide pigment at 162 °C.

Volume explains why that limit matters: about a quarter of the roughly 250,000 t of organic pigment produced in 2006 were diarylide yellows, and in plastics the class is limited to PVC and low-temperature polyolefin processing. C.I. Pigment Yellow 83 (PY83, CAS 5567-15-7), a reddish yellow registered at 1,000 to 10,000 t a year, colours flexible PVC and printing inks on plastics and is not listed in 21 CFR 178.3297. The processing-temperature warning is set out for Pigment Yellow 83.

A seventh yellow sits beside the diarylides: PY155 (CAS 68516-73-4) is a bisacetoacetarylide disazo yellow whose formula, C34H32N6O12, carries no chlorine and therefore no dichlorobenzidine unit.

4. Disazo condensation pigments: PY93, PY95 and PR166#

Disazo condensation pigments are large two-azo-group molecules, from 794.5 g/mol for PR166 to 937.0 g/mol for PY93, and the 3 profiled here, C.I. Pigment Yellow 93 (PY93, CAS 5580-57-4), Pigment Yellow 95 (PY95, CAS 5280-80-8) and Pigment Red 166 (PR166, CAS 3905-19-9), appear in ECHA's mapping in all 11 polymer groups from polyolefins to polycarbonate. That listing, each at 2 wt%, records presence, not a heat rating. EU registration is 100 to 1,000 t a year for PY93 and PR166 and 10 to 100 t a year for PY95. The red of the class is profiled on Pigment Red 166 (disazo condensation red).

5. Benzimidazolone pigments: PY151, PY154, PY180, PO36, PO64 and PR176#

Benzimidazolone pigments are azo pigments carrying a benzimidazolone group, and the 6 profiled for plastics run from the yellows C.I. Pigment Yellow 151 (PY151, CAS 31837-42-0) and Pigment Yellow 154 (PY154, CAS 68134-22-5) through Pigment Yellow 180 (PY180, CAS 77804-81-0) to the oranges PO36 (CAS 12236-62-3) and PO64 (CAS 72102-84-2) and the carmine PR176 (CAS 12225-06-8). PY151, registered at 1,000 to 10,000 t a year, appears in ECHA's mapping in polyolefins, PVC, ABS and polystyrene, and PR176 in polyurethane, PVC, ABS and PET.

PY180 is the yellow chosen when a diarylide is ruled out. The disazo benzimidazolone is a dichlorobenzidine-free alternative to diarylide yellows, and 21 CFR 178.3297 lists it at up to 1.0 % by weight of the polymer under conditions of use B through G. Its FDA conditions are detailed on Pigment Yellow 180 (benzimidazolone yellow), which is registered in the EU at 100 to 1,000 t a year.

6. Metal-complex azo pigments: Pigment Yellow 150#

Pigment Yellow 150 (PY150, CAS 68511-62-6) is the one metal-complex azo pigment profiled here: a nickel azobarbiturate complexed with melamine, with no single formula, which ECHA's mapping lists in polyolefins, polyurethane, PVC, ABS, PET, PA and PC. Its nickel brings the lowest numeric metal limit in EU food contact, 0.02 mg/kg of food under Annex II of Regulation (EU) No 10/2011. PY150 is registered at 100 to 1,000 t a year. Identity and registration are on Pigment Yellow 150 (nickel azo yellow).

7. Phthalocyanine pigments: PB15, PG7 and PG36#

Phthalocyanine pigments are copper complexes of a large conjugated macrocycle, and they make up about 25 % of all synthetic organic pigments, led by phthalocyanine blue C.I. Pigment Blue 15 (PB15, CAS 147-14-8) and phthalocyanine green C.I. Pigment Green 7 (PG7, CAS 1328-53-6). Copper phthalocyanine was first prepared in 1927 and sold by ICI as Monastral blue, and Patrick Linstead at Imperial College solved its structure.

PB15 (C.I. 74160) is registered in the EU at 10,000 to 100,000 t a year, and is listed with its crystal forms in 21 CFR 178.3297 without a numeric limit. The beta form PB15:3 is profiled on Pigment Blue 15:3 (phthalocyanine blue), including why the early alpha grades flocculated with rutile titanium dioxide.

Chlorination shifts the absorption from blue to green, which turns the blue into PG7 (C.I. 74260), a mixture of chlorination degrees registered at 1,000 to 10,000 t a year and also listed in 21 CFR 178.3297 without a numeric limit. The brominated and chlorinated PG36 (CAS 14302-13-7, C.I. 74265) is the yellower green, although ECHA CHEM now shows its registration under that CAS as ceased manufacture, and it is not listed in 21 CFR 178.3297.

8. Quinacridone pigments: PV19, PR122 and PR202#

Quinacridone pigments are hydrogen-bonded polycyclic pigments that run from red to violet and magenta: C.I. Pigment Violet 19 (PV19, CAS 1047-16-1) is the parent quinacridone, Pigment Red 122 (PR122, CAS 980-26-7) its 2,9-dimethyl and Pigment Red 202 (PR202, CAS 3089-17-6) its 2,9-dichloro derivative. PV19 (C.I. 73900) and quinacridone magenta PR122 are each registered at 1,000 to 10,000 t a year and PR202 at 100 to 1,000 t a year. Red, violet and magenta masterbatch, automotive plastics and fibres are the recorded applications of PV19.

The three differ in US food-contact status as much as in shade: 21 CFR 178.3297 lists PV19, as quinacridone red, without a numeric limit and PR202 at up to 1.0 % by weight, but does not list PR122. Crystal forms and nucleation are covered on quinacridone (Pigment Violet 19). Quinacridone also changes how polypropylene crystallises: H. J. Leugering identified gamma-quinacridone as a beta nucleating agent for PP in 1967 (Makromolekulare Chemie 109:204).

9. Diketopyrrolopyrrole (DPP) pigments: PR254, PR264 and PO73#

Diketopyrrolopyrrole (DPP) pigments are hydrogen-bonded red and orange pigments, C.I. Pigment Red 254 (PR254, CAS 84632-65-5), Pigment Red 264 (PR264, CAS 88949-33-1) and Pigment Orange 73 (PO73, CAS 84632-59-7), that combine high heat stability with one marked weakness: they are not stable to acid and base. PR264 is a bis(biphenyl) rubine and PO73 a bis(tert-butylphenyl) orange of the same chemistry, sold as IRGAZIN DPP ROT 4013A and IRGAZIN DPP ORANGE 16A.

PR254 is the reference DPP red, its chromophore held in the crystal by strong intermolecular hydrogen bonding, so the polymorph of a grade counts. It is registered in the EU at 1,000 to 10,000 t a year as a notified new substance, and 21 CFR 178.3297 lists it at up to 1 % by weight of the polymer under conditions of use B through H. Red masterbatch, automotive plastics and housewares are its recorded uses, and it is named as the replacement for the restricted lead chromate molybdate red PR104. The reference DPP red is profiled on Pigment Red 254.

10. Perylene pigments: PR149, PR178, PR179 and PV29#

Perylene pigments are perylene diimides that give deep reds, maroons and violets, and the 4 profiled here, C.I. Pigment Red 149 (PR149, CAS 4948-15-6), Pigment Red 178 (PR178, CAS 3049-71-6), Pigment Red 179 (PR179, CAS 5521-31-3) and Pigment Violet 29 (PV29, CAS 81-33-4), are listed by ECHA at 2 wt% across almost every polymer group of its mapping. Two of them are listed for food contact in 21 CFR 178.3297, PR179 and PV29, each at up to 1 % by weight of the polymer under conditions of use B through H. PR179 is the N,N'-dimethyl diimide known as perylene maroon, PV29 the unsubstituted perylene diimide, and PR149, PR178 and PR179 are each registered at 100 to 1,000 t a year against 1 to 10 t a year for PV29. The FDA-listed perylene maroon is profiled on Pigment Red 179 (perylene maroon).

11. Isoindoline and quinophthalone yellows: PY139, PY185 and PY138#

Isoindoline and quinophthalone yellows are the polycyclic alternative to the diarylide yellows: the isoindolines C.I. Pigment Yellow 139 (PY139, CAS 36888-99-0) and Pigment Yellow 185 (PY185, CAS 76199-85-4) and the quinophthalone Pigment Yellow 138 (PY138, CAS 30125-47-4) give yellows without a dichlorobenzidine backbone. PY138 carries one of the most specific US food-contact entries of any pigment: at most 1 % by weight under conditions of use C through H, for articles not filled above 158 °F (70 °C). The greenish-yellow quinophthalone (C.I. 56300) appears in all 11 groups of ECHA's mapping, while PY139 is registered at 1,000 to 10,000 t a year and recorded in polyolefins, polyurethane and PVC. The higher-tonnage isoindoline is profiled on Pigment Yellow 139 (isoindoline yellow).

12. Dioxazine, anthraquinone and indanthrone pigments: PV23, PR177 and PB60#

Three polycyclic chemistries have one pigment each in plastics: the carbazole dioxazine violet C.I. Pigment Violet 23 (PV23, CAS 6358-30-1), used mainly to shade whites and blues, the anthraquinone red Pigment Red 177 (PR177, CAS 4051-63-2), and the indanthrone blue Pigment Blue 60 (PB60, CAS 81-77-6). PV23 is a blue-violet pigment for violet masterbatch and for shading; it is not listed in 21 CFR 178.3297, and its EU registration tonnage is not confirmed in our sources. PR177, 4,4'-diamino-1,1'-bianthraquinone, is recorded in ECHA's mapping at 1.0 to 2.0 wt% rather than the flat 2 wt% of most organic pigments, and PB60, also known as Vat Blue 4, appears in all 11 mapping groups. The shading role of the dioxazine violet is covered on Pigment Violet 23 (dioxazine violet).

Azo vs Polycyclic Pigments: Which Group Does a Plastic Need?#

Polycyclic pigments are the group for engineering plastics, outdoor parts and most food-contact shades, while azo pigments cover the high-volume yellows, oranges and reds of PVC and low-temperature polyolefins, provided the processing temperature stays below the limit of the class chosen. The split follows the chemistry: the diarylides, the highest-volume azo class, decompose above about 200 °C, while the fused-ring polycyclic classes are the ones used in engineering plastics. The table below compares the two groups on 4 criteria.

The US food-contact listings sit on the polycyclic side: 8 of the 19 polycyclic pigments profiled here carry a 21 CFR 178.3297 entry, against 1 confirmed entry, PY180, among the 25 azo pigments. The melt temperature decides first, then the service life, then the food-contact rule.

What makes an organic pigment "high-performance"?#

A high-performance organic pigment is an organic pigment chosen for durability rather than cost: in trade usage the term covers the polycyclic classes, from phthalocyanines and quinacridones to diketopyrrolopyrroles, perylenes and isoindolines, which survive engineering-plastics processing and long outdoor service. The full trade list adds perinones, isoindolinones and thioindigo pigments to the 6 polycyclic classes of this page.

The label is a group name, not a test result. Performance still varies with crystal form and grade inside a class: the beta form of quinacridone weathers better than the gamma form of the same molecule. Automotive plastics appear among the recorded applications of both PR254 and PV19, yet the data sheet in the polymer of use still decides each grade.

Organic vs Inorganic Pigments: What Is the Difference?#

Organic pigments are carbon-based molecules that colour plastics transparently and strongly at about 2 wt%, while inorganic pigments are metal oxides, sulfides and salts that hide what lies behind them and are dosed at about 5 wt%, so the choice turns on transparency against opacity, then on heat and regulation. Table T2 compares the two pigment groups on 9 criteria, each with its source type.

Table T2. Organic vs inorganic pigments in plastics.

Values are class examples from the sources named, not universal limits; per-grade data come from the supplier's data sheet in the polymer of use.

The shrinkage row is a measured result for two specific greens, not a general rule that one pigment group warps more. The oxides, sulfides and calcined mixed metal oxides are compared grade by grade on inorganic pigments for plastics.

When does an inorganic pigment replace an organic one?#

An inorganic pigment replaces an organic one when the part has to be opaque, when the melt runs hotter than the organic class can survive, or when the shade is an earth tone or buff that the oxides make better; the reverse switch happens when a lead chromate or cadmium pigment has to be replaced. The 3 cases that call for an inorganic pigment are listed below.

1. Opacity: a hiding white or an opaque pastel needs titanium dioxide, typically at about 5 wt%.
2. Heat beyond the organic class: a melt above the limit of the chosen organic class calls for one of the complex inorganic color pigments, the heat and weather reference of the colorant range.
3. Earth tones and buffs: iron oxides and Pigment Brown 24 give the brown and buff shades that the organic classes do not reach economically.

The reverse switch is driven by regulation: lead chromate, PY34 and PR104 have been substances of very high concern since 13 January 2010 and sit on REACH Annex XIV (entries 10 to 12) with a sunset date of 21 May 2015. The organic replacements are the benzimidazolone yellows PY180 and PY181, the isoindolinone PY110, the isoindoline PY139 and the diketopyrrolopyrrole reds and oranges, with PR254 replacing the molybdate red PR104.

Replacing lead chromate is the case where organic and inorganic pigments are blended: DPP reds and benzimidazolone or isoindoline yellows carry the chroma, and bismuth vanadate, PY53, PBr24 or a rutile pigment carries the opacity. Metamerism has to be managed in that switch, because a heavy-metal-free formula can match the old shade under one light source and drift under another.

Which Properties Decide Whether an Organic Pigment Works in a Plastic?#

Five properties decide whether an organic pigment works in a given plastic: heat stability at the melt temperature, lightfastness and weathering, resistance to migration, its effect on the polymer's crystallisation, and resistance to acids and bases. All five are measured in the polymer at the concentration of use, and class-by-class data are collected under pigment fastness in plastics.

Heat stability: why diarylides stop at about 200 °C#

The heat limit of an organic pigment is the temperature at which it starts to decompose or change shade in the melt, and the best documented limit is that of the diarylide yellows, which decompose into monoazo species above about 200 °C, with a first thermogravimetric decomposition peak at 162 °C. Release of 3,3'-dichlorobenzidine is reported above 200 °C, so a diarylide is never specified for a hotter melt.

The polycyclic classes are the ones that pass engineering-plastics melts. Melting points do not translate into processing limits: 390 °C for PV19 and 480 °C for PB15 describe the pure crystal, not the temperature a grade survives in a shearing melt for the residence time of an injection-molded part.

Heat stability is specific to the polymer and the concentration, so the value to compare is the supplier's figure measured in the polymer being run.

Lightfastness and weathering#

Lightfastness in an organic pigment depends on the class and on the crystal form: the beta form of quinacridone weathers better than the gamma form of the same molecule, which is why the grade, not only the C.I. name, has to be specified for outdoor parts. Suppliers rate outdoor performance with accelerated weathering tests such as xenon-arc and QUV exposure, and the rating is only comparable when the polymer and the exposure method match. PR254 and PV19 both list automotive plastics among their recorded applications, the use where weathering decides the grade.

Migration and bleeding#

An organic pigment stays put only as long as it stays insoluble: the fraction that dissolves in the polymer can bleed into a material in contact, bloom to the surface or plate out on the tool, and the risk is highest where a colorant meets a semi-crystalline polyolefin. Solubility in the polymer drives all 3 effects, which is why dyes, which dissolve by design, migrate in polyethylene and polypropylene while insoluble pigments are the polyolefin colorant. No per-pigment migration rating is recorded in our sources, so no grade is called migration-free here. Test methods and the three migration modes are covered under colorant migration in plastics.

Nucleation, shrinkage and warpage#

Organic pigments can nucleate semi-crystalline polymers and so change how a moulded part shrinks: in a 2023 study in the International Journal of Molecular Sciences, a transparent phthalocyanine masterbatch at 1 to 5 wt% raised flow-direction shrinkage in polypropylene by 13.6 to 22.3 % relative to the neat polymer. Shrinkage rose nearly linearly with masterbatch concentration, and the opaque chromium and copper oxide masterbatch in the same study raised it by 49.5 to 58.3 %.

Not all organic classes nucleate equally: phthalocyanines nucleate polypropylene slightly more efficiently than quinacridones. Part design, gate position and pigment grade are compared under pigment-induced warpage. The parts where nucleation shows are injection-moulded PP and HDPE crates, closures and caps, and the answer there is a non-warping or surface-treated pigment grade.

One pigment does more than nucleate. Gamma-quinacridone induces the beta crystal form of polypropylene, the effect H. J. Leugering reported in 1967, and a nucleating pigment can work against a nucleating agent added for cycle time. Calcium pimelate and the other beta nucleating agents are compared with quinacridone on their own page.

Chemical resistance: acids, bases and the DPP exception#

Chemical resistance is the property where the diketopyrrolopyrrole (DPP) pigments PR254, PR264 and PO73 have a documented weakness: they are stable to heat but not to acid and base, so parts that meet cleaning agents or acidic contents need that checked. Our sources record no comparable acid or base data for the other 11 organic classes, so their resistance is a question for the supplier's data sheet rather than an assumed strength.

Which Organic Pigment for Which Polymer?#

The polymer decides the organic class by its melt temperature first: diarylide and other classical azo pigments belong in PVC and polyolefins processed below about 200 °C, while polyamide, polycarbonate and other hot engineering plastics need polycyclic pigments, and semi-crystalline PP and PE add a warpage check. Table T3 sets out 8 polymer rows with the organic classes found in each, the point to watch and one sourced value.

Table T3. Organic pigment selection by polymer.

Classes listed are those ECHA's plastic additives mapping records in each polymer, at a typical 2 wt%, or that a KB card names. A listing shows use, not suitability at every processing temperature: the diarylides appear in the mapping for PA, PC and PET although they decompose above about 200 °C.

Polyolefins: PE and PP#

PE and PP are coloured with organic pigments rather than dyes, because a dye migrates in a semi-crystalline polyolefin, and the two checks for every grade are the processing temperature and the pigment's effect on crystallisation. Diarylide yellows stay below their 200 °C onset, which confines them to low-temperature polyolefin processing.

Phthalocyanines raise PP shrinkage measurably, as the warpage section above shows. A nucleating pigment and the nucleating agents for polypropylene added for cycle time act on the same crystallisation, so they have to be specified together, with a non-warping pigment grade where the part is a crate, closure or cap.

PVC#

PVC is where the classical azo pigments do most of their work: diarylide yellows such as PY83 colour flexible PVC, and PY14 and the barium lake PR53:1 appear in ECHA's mapping almost only for PVC and polyolefins. The benzimidazolones PY151 and PR176, the isoindoline PY139 and the nickel complex PY150 are also recorded in PVC. The old lead chromate yellows have left by regulation: lead in PVC is limited to below 0.1 % w/w from 29 November 2024 under REACH Annex XVII entry 63 (Regulation (EU) 2023/923), with recovered rigid PVC allowed up to 1.5 % until 28 May 2033.

The 200 °C diarylide onset is the only processing number recorded for the class. The stabilizer and lubricant package that the pigment shares is set out in additives for PVC.

Styrenics, PC, PMMA and PET#

In polystyrene, ABS, polycarbonate, PMMA and PET, an organic pigment competes with the solvent dye: the pigment gives opaque and translucent colours, the dye the fully transparent ones, and in food-contact PET the US listings narrow the pigment choice to grades such as PY180, PY138, PR254, PR179 and PV29. ECHA's mapping records perylenes, quinacridones, disazo condensation pigments and PO73 in polycarbonate. Bottle, fibre and film grades each carry their own colorant rules, which are set out in additives for PET.

Polyamides and other high-temperature polymers#

Polyamide is the hardest polymer for an organic pigment, because its melt is both hot and chemically reducing, so the candidates come from the polycyclic classes, such as the perylenes, quinacridones and PB60, and from the metal-complex PY150, never from the diarylides. ECHA's mapping records the perylenes, the disazo condensation pigments, PR177, PB60 and PY150, among others, in polyamide, a list of presence that the supplier's heat data in PA6 or PA66 has to confirm grade by grade. Few dyes survive the same melt, which is why Lanxess launched Macrolex Orange HT specifically for brilliant orange in polyamide. Heat stabilizers and nucleants for PA6 and PA66 are covered in additives for nylon (polyamide).

How Much Organic Pigment Does a Plastic Need?#

An organic pigment is typically used at about 2 wt% of the compound, the value ECHA's mapping gives for most organic pigments, inside the 0.01 to 5 wt% band that covers all colorants in a finished plastic. The 0.01 to 5 wt% band comes from Chea and colleagues (2025), adapted from Hahladakis and colleagues (2018). The 4 concentration conventions that buyers meet are compared below, each with its basis.

Pigment powder is rarely dosed directly. It reaches the machine as color masterbatch with 40 to 65 wt% active content, let down at 1 to 5 % of the base polymer, so a 50 wt% masterbatch let down at 4 % puts 2 wt% of pigment into the part. A dose of 25 kg of masterbatch per tonne equals a let-down of 2.5 %.

The percentages in 21 CFR 178.3297, such as the 1 % cap on PR254, are legal maxima for food-contact articles, not dosage recommendations, and they are expressed as % by weight of the polymer.

How Is an Organic Pigment Tested in a Plastic?#

An organic pigment is tested in the polymer it will colour, for 5 things: colour difference from the standard in CIELAB, dispersion quality, heat stability at the melt temperature, weathering, and, in semi-crystalline polymers, shrinkage of a moulded part. Table T4 lists the 6 tests, with yellowness added for naturals and whites shaded with organic toners, and the reference that applies to each.

Table T4. Tests for an organic pigment in a plastic.

Colour data in older specifications can still be given in CIE Yxy (1931), so the colour space has to be stated with every tolerance. Tolerances, illuminants and metamerism are explained under color measurement and matching of plastics. Heat stability and lightfastness conditions differ by supplier and polymer, so the polymer, concentration and residence time belong to every result.

How Are Organic Pigments Regulated?#

Organic pigments are regulated mainly through food-contact rules and through limits on the metals and impurities they can carry, and none of the 44 organic pigments profiled here is on the REACH Candidate List of substances of very high concern (ECHA CHEM, checked 22 September 2026). The restricted colorants on the SVHC Candidate List are inorganic: lead chromate, PY34 and PR104 since 13 January 2010 and cadmium sulphide since 16 December 2013.

Food contact: 21 CFR 178.3297, EU 10/2011 and AP(89)1#

In the United States an organic pigment for a food-contact plastic has to be listed in 21 CFR 178.3297 or cleared by another route, and the section lists phthalocyanine blue, phthalocyanine green and quinacridone PV19 without a numeric limit while capping PR254, PR179 and PV29 at 1 % by weight of the polymer. Every entry of 21 CFR 178.3297 carries the good-manufacturing-practice condition that levels must not exceed those reasonably required, and colour additives listed in 21 CFR parts 73, 74, 81 and 82, with their lakes, may also be used. Table T5 gives the status of 14 organic pigments.

Table T5. Food-contact status of 14 organic pigments.

21 CFR 178.3297 percentages are legal maxima for food-contact use under the stated conditions of use, not dosage recommendations. "Not listed" means absent from 178.3297 by name and CAS (eCFR current to 18 September 2026); clearance by a Food Contact Notification or another route is not verified. "Not on the Union list" means outside Regulation (EU) No 10/2011; national rules and Resolution AP(89)1 apply.

The EU takes the opposite route. Organic pigments sit outside the Union list of EU 10/2011, so they have no FCM number and no specific migration limit of their own, but the Annex II metal limits apply to every coloured article (consolidated text of 14 July 2026): copper 5 mg/kg, barium 1 mg/kg, cobalt 0.05 mg/kg and nickel 0.02 mg/kg of food, with cadmium, chromium, lead, mercury and arsenic not detectable. The overall migration limit of 10 mg/dm2 (60 mg/kg for infant articles) covers the article as a whole, and nanoforms are usable only where explicitly authorised (Article 9(2)).

Purity requirements for colorants in EU food-contact plastics come from national rules and from Council of Europe Resolution AP(89)1, whose limits are set out on its own page rather than repeated here. Japan applies its own prerequisite through the JCII: food-contact colorants may contain at most 100 ppm lead, 50 ppm mercury and 100 ppm cadmium, and the JCII Food Contact Materials Safety Center took over the former JHOSPA certification from 1 April 2021.

Dichlorobenzidine, metal migration and packaging limits#

Outside food contact, three rules shape the choice of an organic pigment: the dichlorobenzidine caveat on diarylide yellows above about 200 °C, the EU limits on metals that migrate from a coloured article, and the PPWR cap of 100 mg/kg on lead, cadmium, mercury and hexavalent chromium in packaging from 12 August 2026. The first is a processing rule: diarylide yellows (PY12, PY13, PY14, PY17, PY83 and PO13) are reported to release 3,3'-dichlorobenzidine above about 200 °C, in virgin processing or in recycling.

The second rule follows the metal in the molecule: copper phthalocyanines answer to the 5 mg/kg copper limit, barium lakes such as PR53:1 to the 1 mg/kg barium limit and PY150 to the 0.02 mg/kg nickel limit of Annex II.

The third rule caps lead, cadmium, mercury and hexavalent chromium together at 100 mg/kg in packaging. The cap sits in Article 5(4) of the Packaging and Packaging Waste Regulation (PPWR), Regulation (EU) 2025/40. None of the organic pigments profiled here contains lead, cadmium, mercury or chromium in its formula, PY150 included, so the cap bites on the inorganic heavy-metal pigments that organic pigments replace rather than on the organic classes themselves.

Who Makes Organic Pigments for Plastics?#

Organic pigments for plastics come mainly from three groups after a decade of consolidation: DIC with Sun Chemical, after DIC closed its acquisition of BASF Colors & Effects in 2021, Sudarshan, which completed its acquisition of Heubach, including the former Clariant pigments, on 3 March 2025, and Toyo. Company profiles and plants are in the directory of pigment manufacturers and suppliers. Table T6 lists the producers our knowledge base names, without a ranking.

Table T6. Organic pigment producers in our knowledge base.

Producers named in our knowledge base for organic pigments; trade names on the substance pages are ECHA-registered trade names and are not attributed to a company unless stated.

Buyers should compare offers by C.I. name, CAS number and crystal form, since one C.I. name covers grades that differ in heat stability, warpage and dispersion. Trade names such as Sudaperm, Hostaperm, Paliogen, Paliotol and IRGAZIN are resolved to C.I. names and CAS numbers in the plastic additive trade name lookup.

Complete List of Organic Pigments for Plastics: 44 Pigments#

The 44 organic pigments profiled on this site are listed below in the order of the 12 classes, with their CAS number, hue, the polymers ECHA's mapping records them in, their EU registration band and their US food-contact status. Table T7 holds 25 azo pigments (classes 1 to 6) and 19 polycyclic pigments (classes 7 to 12).

Table T7. 44 organic pigments for plastics.

* Mapping listings show where a pigment is found, not where it is suitable: diarylide yellows decompose above about 200 °C. "Not established" means no entry in our sources; it is not a statement that the pigment is absent from 21 CFR 178.3297. "PO" = the two polyolefin groups of ECHA's mapping. EU REACH bands from ECHA CHEM, checked 22 September 2026.

Every row leads to a substance page with identity, dosage, regulatory matrix and suppliers.

Are Organic Pigments Safe and Recyclable?#

None of the 44 organic pigments profiled here is a substance of very high concern, but two findings matter once a coloured plastic is reheated: diarylide pigments decompose above about 200 °C, and in a 2025 study in Materials all three printing-ink pigments tested were mutagenic in miniaturised Ames tests after 30 minutes at 240 °C. The same study, carried out by Fraunhofer IVV and OFI, found 4 of 13 printed foils positive, a result for heated printing-ink pigments, not for pigment bound in a moulded part at room temperature. PY83, the reference diarylide, has no harmonised classification, and some notifiers report H335. Substances of real concern in plastics are listed on toxic plastic additives.

Organic pigments in recycled plastics#

Organic pigments follow the plastic into recycling, and the diarylide yellows of printing inks are the documented problem: their decomposition products have been identified as the cause of yellowing in solvent-recycled polyethylene. The 3 documented recycling effects of organic pigments are listed below.

• Diarylide decomposition products: identified as the cause of yellowing in solvent-recycled PE (Science Advances, 2025)
• Heated printing-ink pigments: positive in miniaturised Ames tests after 30 minutes at 240 °C (Materials, 2025)
• Dark shades: a colour with L* below 40 or a near-infrared reflectance of 10 % or less fails APR Design Guide clause SORT-S-01

Colour choices that keep a package sortable are set out under how additives affect plastic recyclability.

Organic pigments outside plastics: inks, coatings and cosmetics#

The same C.I. pigments are sold for printing inks, paints and cosmetics, but this reference covers them only as plastics colorants, where the pigment must survive the melt rather than dry in a binder. PY83 colours printing inks on plastic film as well as flexible PVC, yet the performance data, loadings and regulatory limits of ink, paint and cosmetic uses do not transfer to a polymer melt, so artists' colour, cosmetic and permanent make-up pigments are not covered here.

Are organic pigments natural pigments?#

No: the organic pigments used in plastics are synthetic industrial chemicals, and "organic" refers to their carbon-based chemistry, not to a natural origin or to organic certification. Every one of the 44 pigments profiled here is identified by a CAS number as a manufactured substance.

What are inorganic pigments?#

Inorganic pigments are metal oxides, sulfides and salts, such as titanium dioxide, carbon black, iron oxides and the calcined mixed metal oxides, that colour and hide at the same time. The reference white, titanium dioxide, is dosed at about 5 wt% in ECHA's mapping, more than twice the typical 2 wt% of an organic pigment.

Is a pigment that contains copper or nickel still organic?#

Yes: phthalocyanine blue contains copper and PY150 contains nickel, but both are organic pigments because their colour comes from a carbon-based chromophore; the metal only changes which EU migration limit applies. That limit is 5 mg/kg for copper and 0.02 mg/kg for nickel under Annex II of Regulation (EU) No 10/2011.

What is the difference between an organic pigment and an organic dye?#

An organic pigment stays insoluble in the plastic and colours as a particle, while an organic dye such as Solvent Red 135, Solvent Yellow 114, Solvent Violet 13 or Solvent Blue 97 dissolves in the melt and gives a transparent colour. Dyes suit amorphous polymers such as polystyrene, PMMA and polycarbonate and migrate in polyolefins, where the 44 pigments above do the colouring.

Are fluorescent pigments organic pigments?#

Fluorescent pigments are a separate colorant type: they are fluorescent dyes dissolved in a resin carrier and ground to a powder, so they behave as particles in the polymer while their colour comes from a dissolved dye. Their carriers, loadings and limits are covered on fluorescent pigments for plastics.