Black Masterbatch: 5 Specifications, Carbon Black Loadings and Let-Down Ratios

Black masterbatch is a concentrate of carbon black pigment dispersed in a carrier resin and supplied as pellets, which a converter dilutes into natural polymer at 1-5 % to colour the part black and screen it from ultraviolet light. Two black masterbatches at the same price can differ by a factor of two in carbon black content and by a whole grade in particle size, so which specifications actually decide what arrives in the finished part? Ampacet gives 35 wt% carbon black as the North American industry standard for pressure applications, and that single number, not the price per kilogram, is what fixes how much masterbatch a formulation needs.

Carbon black is the single highest-volume black colorant among plastic additives, and it reaches most converters as a masterbatch rather than as powder. Every other additive function that sits next to masterbatch in a formulation, from plasticizers to flame retardants, is classified on the plastic additives hub, alongside the dosage conventions this page uses for carbon black.

This page sets out what black masterbatch is made of, the 5 specifications a data sheet must answer, how the let-down ratio is calculated in both conventions, how much carbon black each application actually carries, whether the pigment replaces a light stabilizer, how the masterbatch is tested, which food-contact and drinking-water limits apply, why black plastic fails near-infrared sorting, and which companies supply it.

Key figures

• Masterbatch active content: 40-65 wt% typically, 15-80 wt% in extreme cases
• North American pressure-pipe standard: 35 wt% carbon black in the masterbatch, with grades above 40 wt% avoided
• Pressure-pipe let-down: 5.7-7.1 % (about 16.5:1 to 13:1) of a 35 wt% masterbatch to reach the 2.0-2.5 wt% the standard requires; the 5-6.5 % (19:1 to 14:1) Ampacet publishes delivers only 1.75-2.28 wt%
• Food-contact ceiling: 2.5 % w/w maximum carbon black in the polymer, in both the EU and the US

What Is Black Masterbatch?#

Black masterbatch is the black-pigmented member of the masterbatch family: a carbon black concentrate in a carrier resin that lets a converter dose a few percent of pellets instead of handling a fine, dusty pigment powder. It carries 40-65 wt% active content in the general case, with extremes down to 15 wt% and up to 80 wt%, and is diluted into the base polymer at 1-5 % to reach the colour and additive levels the part needs.

Dosing a concentrate this way has 4 advantages over adding neat pigment:

• More accurate dosing of an expensive additive
• Less airborne dust on the production floor
• Longer shelf life than a solvent-based colour system
• The option to combine several masterbatches, for example a black pigment concentrate and a separate antioxidant concentrate, on the same feed throat

The hub on masterbatch compares every concentrate type against these same advantages and sets out the let-down conventions every masterbatch page on this site shares.

What is black masterbatch made of?#

A black masterbatch has 4 components: carbon black, a carrier resin or wax, a dispersing aid, and, in additive-carrying grades, the functional additives themselves.

• Carbon black (CAS 1333-86-4, EC 215-609-9, C.I. Pigment Black 7): the pigment itself, made by incomplete combustion of hydrocarbon feedstocks, with the process, furnace, channel, lamp, thermal or acetylene black, setting the particle size and structure of the finished grade
• Carrier resin or wax: the vehicle the pigment is dispersed into before pelletising
• Dispersing aid: the chemistry that keeps the pigment wetted and evenly spread through the carrier
• Functional additives: present only in combination grades, alongside the carbon black in the same pellet

Furnace black is the dominant industrial route; channel black and the other processes appear mainly in speciality or legacy grades.

The carrier is chosen to match the base polymer: wax works as a universal carrier across families, while EVA or LDPE carries the pigment for polyolefins and nylon, and polystyrene carries it for ABS, SAN and, in some formulations, polycarbonate. Carbon black is one entry in the wider family of colorants for plastics, which the colorant hub classifies by chemistry rather than by delivery form. Whether the pigment is premixed with the carrier or fed by a side feeder downstream of the melting zone is explained under how masterbatch is made, a page this site is building next.

Black masterbatch vs carbon black powder vs pre-coloured compound#

Black masterbatch sits between neat carbon black powder and a ready-made black compound: the powder is cheapest per kilogram of pigment but dusty and hard to disperse, the compound needs no dosing at all but locks the converter into one supplier's base resin, and the masterbatch keeps the converter's own resin while dosing the pigment accurately. Two production routes deliver that dosing accuracy. In split-feed compounding, polymer pellets enter the main feed and the pigment is added by a twin-screw side feeder downstream of the melting zone, giving gentle wetting and fewer agglomerates. In premix compounding, all components are premixed and fed volumetrically, a simpler line with less control over wetting.

Table T1: masterbatch vs powder vs compound

Concentration ranges are generic masterbatch values; a specific grade's loading is on its data sheet.

What Are the 5 Specifications of a Black Masterbatch?#

The 5 specifications that decide what a black masterbatch does in a part are the carbon black grade and its primary particle size, the carbon black loading in the concentrate, the carrier resin, the dispersion rating and the dispersing-aid package; the grade and the loading decide most of the cost. They are read on a data sheet in that order, and the checklist below (Table T2) follows the same sequence.

1. Carbon black grade and primary particle size#

Primary particle size is the first specification on a black masterbatch data sheet because it sets three things at once: jetness, ultraviolet screening and how hard the pigment is to disperse. Carbon black is supplied as a black powder or beads that sublime above 3,500 °C; its primary particles fuse into aggregates, described as the pigment's structure, which in turn loosely form agglomerates that dispersion has to break apart. Ampacet's pipe-compound guidance gives an N550-type black at a nominal 40-48 nm as generally sufficient, moving to a finer N330 type (26-30 nm) or an N110 type (below 20 nm) when outdoor exposure runs longer than 3-5 years. That guidance describes North American practice under ASTM D3350, which asks only for a black with at least 2 % carbon black and sets no particle size; ISO 4427-1 requires an average primary particle size of 10 to 25 nm, which only an N110-type black satisfies.

Finer is not automatically better: the same property that raises ultraviolet protection also raises the dispersion effort, so the grade is chosen against the expected service life, not against the darkest possible black. Identity, grades and the full regulatory record for carbon black in plastics sit on the substance page.

Table T3: carbon black grades named for pipe compounds

Particle sizes and use guidance from Ampacet's pipe-compound FAQ; the ASTM N-number itself is a rubber-industry classification carried over into plastics.

2. Carbon black loading in the masterbatch#

Carbon black loading in the concentrate is the number that decides the let-down ratio, and Ampacet gives 35 wt% as the North American standard for pressure applications, with masterbatches above 40 wt% to be avoided because the pigment can no longer be wetted properly. That 35 wt% figure is a pressure-pipe value from a named supplier, not a rule for black masterbatch in general: masterbatches as a class carry 40-65 wt% active content, with extremes from 15 wt% to 80 wt%, and a specific black grade can sit anywhere in that range depending on its intended application.

Buyers compare loading only against a stated basis, because a 35 wt% grade and a 55 wt% grade require different let-down ratios to deliver the same carbon black level in the part, a calculation set out under How Much Black Masterbatch Do You Add.

3. Carrier resin#

The carrier resin has to melt and mix into the base polymer without leaving unmelted cores, which is why Ampacet specifies an MLDPE or LLDPE carrier with a melt index below 20 g/10 min for pressure-pipe black masterbatch. A universal, wax-based carrier buys compatibility across polymer families at the cost of some of the base polymer's own properties, while a polymer-specific carrier is the default wherever the compound is tightly specified, as it is in pressure pipe. Unmelted concentrate and a mismatched carrier are named causes of gels in PE film, alongside poor pigment dispersion, and the fixes include smaller masterbatch pellets, a carrier change and tighter screen packs.

Universal and polymer-specific carriers are compared in more detail under masterbatch carrier resins, a page this site is building next.

4. Dispersion rating#

Dispersion is the specification that separates two masterbatches with identical carbon black content: Ampacet reports it on a 1-to-5 microdispersion scale, where 1 is best, measured on roughly 1.5 mil cast film and stated for every production lot. Pigment and carbon black dispersion in polyolefin pipe compounds is additionally rated to ISO 18553, the standard method the pipe industry uses alongside a producer's own in-house scale.

Buyers should ask for the dispersion rating per lot, not per grade, because it is a production result rather than a fixed formulation property; the same recipe can disperse differently between batches. The methods behind the rating are described under dispersion testing of pigments and masterbatch, a page this site is building next.

5. Dispersing aids and the rest of the carrier package#

Above about 30 wt% pigment, a concentrate needs a dispersing aid to stay processable: dispersing aids such as Palsgaard's Einar 103 are dosed at 1-5 % of a colour masterbatch, and wax-based aids such as Clariant's Licocene are sold as both dispersion aid and carrier, allowing higher pigment loadings at lower processing temperature and shear. Our source library holds no dispersing-aid dosage specific to black masterbatch, so these figures illustrate the principle from a colour-masterbatch source rather than a black-masterbatch one.

The same mechanism shows up in filler masterbatch: a 60 wt% calcium carbonate masterbatch in LLDPE carries 3 times the melt viscosity of the neat polymer, and adding 3 wt% wax plus 1.0 wt% zinc stearate brings that viscosity back to just above neat. Chemistries and dosages of dispersing agents for plastics and masterbatch are set out on the dispersant hub.

Table T2: specification checklist

Ask for all six on the technical data sheet before comparing prices per kilogram.

Download the Black Masterbatch Specification Checklist (PDF): the 6 questions to ask before comparing prices per kilogram.

How Much Black Masterbatch Do You Add?#

Black masterbatch is normally added at 1-5 % of the base polymer, with pressure-pipe grades at the upper end, because the addition rate is not a preference but the result of dividing the carbon black the part needs by the carbon black the concentrate contains. A pressure-pipe black masterbatch at 35 wt% carbon black is added at 5-6.5 %, expressed equally as a ratio of 19:1 to 14:1 of resin to masterbatch.

How to calculate the let-down ratio#

The let-down ratio is the dilution of masterbatch into natural resin, and it is quoted in two conventions that look different but mean the same thing: as a percentage of the blend (5 %) or as a ratio of resin to masterbatch (19:1). The calculation runs in 3 steps:

1. Find the carbon black level the part specification requires, expressed as wt% in the finished part.
2. Divide that level by the carbon black content of the masterbatch to get the masterbatch fraction of the blend.
3. Convert that fraction into both conventions: a percentage of the blend, and a ratio of natural resin parts to one part masterbatch.

As a worked example, a 35 wt% masterbatch at a 5 % let-down delivers 0.35 x 5 % = 1.75 wt% carbon black in the part, and the same masterbatch at a 6.5 % let-down delivers 0.35 x 6.5 % = 2.3 wt% carbon black. Always give both conventions on first use: a reader who mistakes "1:50" for "50 parts masterbatch" over-doses the part by a factor of 2,500. Check both conventions against the same numbers in the let-down ratio calculator.

Table T4: let-down conversion

Arithmetic from the masterbatch loading; the 35 wt% and 5-6.5 % values are Ampacet's North American pressure-pipe standard. A 2.5 % w/w food-contact ceiling on carbon black is reached at 6.5 % let-down of a 40 wt% masterbatch.

Let-down ratios and carbon black levels by application#

The let-down ratio follows from the carbon black level the application specifies, and only two of those levels are set by a standard: 2.0-2.5 wt% for PE pressure pipe and 2.0-3.0 wt% for HDPE geomembranes. Film, cable, injection-moulded parts and recyclate each have a driver for their carbon black level, opacity, service life or conductivity, but no published standard figure exists for them in our source library, so their level is set by the individual part specification rather than by an industry number. Typical levels for every other additive family are collected under additive dosage levels in plastics, a page this site is building next.

Table T5: master application table

Standard values are the carbon black content of the compound, not of the masterbatch. Supplier let-down figures are starting points; trials decide the final level.

Request quotes for black masterbatch: carbon black loading, carrier resin, base polymer, volume, country. Find suppliers with the plastic additive supplier finder

Which Black Masterbatch Suits Each Application?#

The right black masterbatch depends on the service life outdoors, the carrier's compatibility with the base resin and whether the part must later be sorted or must meet a food-contact limit, which is why the same 35 wt% concentrate is right for a buried pipe and wrong for a packaging tray.

HDPE and PE100 pressure pipe#

PE pressure pipe is the most tightly specified use of black masterbatch: EN 12201-1 and ISO 4427-1 put 2.0-2.5 wt% carbon black in the compound and require a compound oxidation induction time of at least 20 minutes at 210 °C. The standard itself specifies a primary particle size of 10-25 nm for that carbon black, in clause 5.2.1; Ampacet's own pipe-compound guidance, by contrast, names an N550-type black at 40-48 nm as generally sufficient, moving finer only for long outdoor exposure. The two are not equivalent and the standard decides: Ampacet describes North American practice under ASTM D3350, which sets no particle size, so of the grades it names only an N110-type black falls inside the 10-25 nm band. Reaching the 2.0-2.5 wt% the standard requires from a 35 wt% masterbatch also needs a let-down of 5.7-7.1 %, about 16.5:1 to 13:1, since the 5-6.5 % Ampacet publishes delivers only 1.75-2.28 wt%.

The 2.0-3.0 % figure that circulates for black PE belongs to HDPE geomembranes under GRI-GM13, not to pressure pipe. The rest of the pipe package, from antioxidants to acid scavengers, is on additives for plastic pipes, a page this site is building next. The complete PE formulation, including the oxidation induction time requirement, is on additives for polyethylene.

Agricultural and packaging film#

Film is where dispersion matters most, because an agglomerate that would be invisible in a 3 mm pipe wall shows as a gel or a pinhole in a 25 micron film. Carbon black gives film its opacity and its outdoor light barrier, but no carbon black loading for agricultural or packaging film exists in our source library, so only the driver, not a target percentage, can be stated here. Gels in PE film trace partly to unmelted concentrate and poor masterbatch dispersion, and the fixes are smaller masterbatch pellets, a carrier change and tighter screen packs, the same dispersion rating covered under the specification section above.

Outdoor film packages are covered under additives for agricultural film, a page this site is building next. Slip, antiblock and the rest of the film package are on additives for packaging film.

Wire, cable and conduit#

Cable jacketing uses black masterbatch for the same reason buried pipe does, namely the ultraviolet screen, but a cable specification may also call for a conductive or semi-conductive layer, and that is a different pigment grade entirely. A pigment-grade black masterbatch does not make a compound conductive; conductive carbon black is a separate grade class with its own particle structure and loading level.

Cabot markets the distinction directly: PLASBLAK is its pigment-grade masterbatch line, while CABELEC is sold separately for conductive and semi-conductive compounds, and structure and loading for conductive carbon black are covered on its own page. Jacket and insulation packages for the pigment-grade side are set out under additives for wire and cable compounds.

Injection-moulded and automotive parts#

Injection moulding adds a dimensional question to the colour question, because a pigment that nucleates the polymer changes how the part shrinks in the mould. In a 2023 study published in the International Journal of Molecular Sciences (PMC10298002), injection-moulded PP coloured with a green masterbatch showed relative shrinkage in the flow direction rising from 13.6 % to 22.3 % against neat PP for a transparent phthalocyanine masterbatch, and from 49.5 % to 58.3 % for an opaque chromium/copper-oxide masterbatch, across masterbatch loadings of 1-5 wt%. The study used green pigments, not carbon black, and no shrinkage figure in our source library is attributable to black masterbatch specifically; it demonstrates that pigment choice, not colour alone, changes how a moulded part shrinks.

Interior and exterior packages are on additives for automotive plastics, a page this site is building next.

Recycled and regrind compounds#

Black masterbatch has a second-life problem: carbon black absorbs near-infrared light, so a black part passes a sorting line as an unidentified object and leaves the recycling stream rather than being separated by polymer type. The Association of Plastic Recyclers' Design Guide SORT-S-01 treats black or dark colours with an L* below 40, or a near-infrared reflectance of 10 % or less, as a sortability failure. NIR-detectable black masterbatch grades, such as Ampacet's REC-NIR-BLACK, are COTREP-certified for PP and HDPE rigid packaging as an alternative, and the EU Packaging and Packaging Waste Regulation adds recycled-content and sortability pressure to that choice from 2026 onward.

Restabilization and contamination limits are on additives for recycled plastics.

Does Black Masterbatch Replace a UV Stabilizer?#

Black masterbatch replaces part of a light-stabilizer package but not the whole additive package: carbon black is the most effective ultraviolet screen for polyethylene and polypropylene, absorbing UV light across the solar spectrum in the outer layer of the part, yet it does nothing about thermal oxidation during processing or in service. A black PE pressure-pipe compound still needs its antioxidant package for that reason: the pipe standard's requirement of at least 20 minutes' oxidation induction time at 210 °C is an antioxidant requirement, not a pigment one, and it applies to the compound whether or not carbon black is present.

Carbon black is a screener, not a chemical stabilizer, and it should never be described as a HALS or a UV absorber in the chemical sense; those classes work by different mechanisms and are compared, along with the classes carbon black does not replace, on UV stabilizers for plastics. No lifetime figure for a black compound exists in our source library, so no "lasts X years" claim can be made here, and film and pipe levels for the HALS grades a black compound may still need are set out on UV stabilizers for polyethylene.

How Is Black Masterbatch Tested?#

A black masterbatch is judged on three measurements: how much carbon black it actually contains, how well that carbon black is dispersed, and what colour the let-down film or plaque comes out.

Carbon black content: ASTM D1603 and ISO 6964#

Carbon black content is measured by pyrolysing the sample under nitrogen and weighing the residue, which is the shared principle of both ASTM D1603-20 and ISO 6964. The method is not valid where brominated flame retardants or other non-volatile fillers are present in the compound, because their residue is counted as carbon black along with the pigment itself. Geomembrane compounds tested to GRI-GM13 use ASTM D4218 instead, a related pyrolysis method written for that standard.

Dispersion: ISO 18553 and the microdispersion scale#

Dispersion is rated microscopically: ISO 18553 is the pipe-industry method for pigment and carbon black dispersion in polyolefins, and masterbatch producers additionally report an in-house microdispersion rating, on Ampacet's scale from 1 (best) to 5, measured on about 1.5 mil cast film for every production lot. The two methods answer the same question, how evenly the pigment is broken down into the carrier, at different points in the supply chain: the standard on the finished pipe compound, the producer's scale on the masterbatch itself.

Colour, jetness and undertone#

Blackness is reported in the CIE Lab* colour system, where L* is the lightness axis, and the same L* value that describes a deep black also decides whether the part can be sorted: the APR Design Guide treats an L* below 40 as the threshold at which a colour fails near-infrared sorting. The CIE devised the earlier Yxy colour space in 1931 and the Lab* space in 1976, and plastics colour measurement has used the later system since. How Lab* values are measured and matched is explained under colour measurement and matching of plastics.

Table T6: test methods

Which Black Masterbatch Is Allowed in Food Contact and Drinking Water?#

In the EU, carbon black is listed as an additive under FCM No. 411 at a maximum use level of 2.5 % w/w in the polymer; in the US, high-purity furnace black is cleared under 21 CFR 178.3297 at the same 2.5 % ceiling by weight of the polymer, subject to purity conditions; colorants as a class sit outside both Union lists otherwise. Carbon black is one of only a handful of colorant-type substances with its own EU food-contact entry, alongside titanium dioxide, zinc sulphide, iron oxide, mica, OB-1 and BBOT.

EU 10/2011: FCM 411 and the 2.5 % limit#

FCM No. 411 does more than cap the level: it defines what may be called carbon black in a food-contact plastic, through a primary-particle-size window of 10-300 nm (aggregated to 100-1,200 nm), a toluene-extractables limit of 0.1 % to ISO 6209, a UV-absorption limit on the cyclohexane extract at 386 nm of below 0.02 AU in a 1 cm cell (or 0.1 AU in a 5 cm cell), and a benzo(a)pyrene limit of 0.25 mg/kg of carbon black. Carbon black has no specific migration limit under this entry; the 2.5 % w/w figure is a maximum use level in the polymer, not a migration limit. How the Union list, specific migration limits and the overall migration limit fit together is explained on EU 10/2011.

Table T7: regulatory matrix for carbon black in a black masterbatch

FDA 21 CFR 178.3297: channel black and high-purity furnace black#

US food-contact law splits carbon black by production process: 21 CFR 178.3297 lists channel-process carbon black without a numeric limit and high-purity furnace black at a maximum of 2.5 % by weight of the polymer, with purity conditions of 0.5 ppm total PAH or less and 5.0 ppb benzo[a]pyrene or less. Carbon black is never described as "FDA approved" on this page; it is listed in 21 CFR 178.3297 under the stated purity conditions, and the 2.5 % figure is a legal maximum, not a recommended dosage. The full colorant list and its conditions of use are decoded on the 21 CFR 178.3297 page, which this site is building next.

Drinking-water contact#

Black PE pipe that carries drinking water in the EU relies on carbon black being on the European positive list under Directive (EU) 2020/2184, where it appears as entry 0348 with the same 2.5 % w/w ceiling as in food contact. Our source library holds no national drinking-water scheme values, such as NSF/ANSI 61 or WRAS, for carbon black, so only the EU entry is stated here.

Why Black Plastic Fails NIR Sorting#

Black plastic fails near-infrared sorting because carbon black absorbs the same near-infrared light the sorter uses to read the polymer, so the detector sees no spectrum at all rather than the wrong one. The Association of Plastic Recyclers' Design Guide SORT-S-01 sets 2 industry-guidance thresholds for sortability failure:

• L* below 40 (a lightness measurement in the CIE Lab* system)
• NIR reflectance of 10 % or less

These thresholds are industry guidance rather than law. Alternatives named in our source library include NIR-detectable black masterbatch, such as Ampacet's REC-NIR-BLACK, COTREP-certified for PP and HDPE rigid packaging, along with pigment alternatives such as iron oxide black (PBk11), copper chromite black (PBk28) and the perylene blacks (PBk31, PBk32). The carbon-black-free chemistries are compared under NIR-sortable black colorants, a page this site is building next.

Sortability sits inside a wider design question: every additive that helps or hurts sorting is listed under design for recycling.

The EU Packaging and Packaging Waste Regulation applies from 12 Aug 2026 and limits the sum of lead, cadmium, mercury and hexavalent chromium in packaging to 100 mg/kg or less; it does not itself restrict carbon black, though it raises the design-for-recycling stakes around any colour that defeats NIR sorting. Dates, heavy-metal limits and recycled-content targets are on the EU Packaging and Packaging Waste Regulation (PPWR) page.

Who Supplies Black Masterbatch?#

Black masterbatch comes from two kinds of company: carbon black producers who also compound concentrates, such as Cabot with its PLASBLAK line, and independent masterbatch houses such as Ampacet, Avient and Tosaf who buy pigment and sell dispersion. Buyers should compare grades by carbon black loading, particle size grade and dispersion rating, not by price per kilogram of masterbatch, because two grades at the same price can differ in all three.

Table T8: producers named in our source library

Company data from our source library only; the full directory with locations and certifications is on the supplier page.

Locations, grades and certifications for black masterbatch manufacturers are in the directory, organised by country, application and grade.

Pigment producers sit upstream of the masterbatch houses in that same directory structure, and are listed separately under carbon black manufacturers and suppliers for buyers who want to source the pigment directly.

What moves the pigment cost inside a masterbatch price, from feedstock to freight, is tracked on carbon black price.

Request quotes for black masterbatch: carbon black loading, carrier resin, base polymer, volume, country. Send one specification to several masterbatch houses with the plastic additive supplier finder.

What Other Masterbatch Types Does a Converter Use?#

Black is one concentrate in a family: the same let-down arithmetic and the same carrier rules govern colour, white, filler and additive masterbatch, which a converter often doses on the same production line. Pigment selection and shade matching are on color masterbatch.

Colour, white, filler and additive masterbatch#

Colour masterbatch is let down at 2-4 % (49:1 to 24:1) in pipe, a wider and generally lower range than the black pressure-pipe standard. Four masterbatch types share the same carrier and dosing logic, each carrying a different active chemistry:

• Colour masterbatch: pigments other than carbon black, let down at 2-4 % in pipe applications. Shade matching sits on white masterbatch for the titanium-dioxide case.
• White masterbatch: carries titanium dioxide instead of carbon black, with its own grade and processing limits.
• Filler masterbatch: carries calcium carbonate, at loadings high enough to triple the melt viscosity of the base polymer at 60 wt% filler, unless a wax and stearate package brings it back down. Loadings and the viscosity penalty are covered under filler masterbatch.
• Additive masterbatch: carries a functional chemistry rather than a pigment, for example an antioxidant concentrate at 4 % active giving 1,000 ppm active antioxidant in the part at a 2.5 % let-down. Functional concentrates from antioxidant to antifog are on additive masterbatch.

Is carbon black hazardous?#

The hazard classifications for carbon black are about the powder in the air, not the pigment in the part: California's Proposition 65 lists it as "carbon black (airborne, unbound particles of respirable size)" for cancer since 21 February 2003, and the International Agency for Research on Cancer places it in Group 2B by inhalation. Carbon black carries no harmonised classification under the EU's CLP Regulation, though some notifiers report H319 and H335. Canada's 2011 screening assessment concluded that continued use, including in food packaging, is acceptable because the pigment is bound in a matrix rather than airborne.

Is black masterbatch the same as carbon black?#

No: carbon black is the pigment, and black masterbatch is that pigment pre-dispersed in a carrier resin at a known loading, so the two are not interchangeable in a formulation calculation.

What is the difference between black masterbatch and a black pigment?#

A black pigment is a single colorant such as carbon black (PBk7), iron oxide black (PBk11) or copper chromite black (PBk28); a black masterbatch is a delivery form that may carry any of them, most often carbon black.

Can black masterbatch be used in food packaging?#

Yes, within a ceiling: carbon black is listed for EU food-contact plastics under FCM No. 411 at a maximum of 2.5 % w/w in the polymer, and high-purity furnace black is listed in 21 CFR 178.3297 at a maximum of 2.5 % by weight of the polymer, subject to the purity conditions on each.

Does black masterbatch make plastic UV resistant?#

Partly: carbon black is the most effective ultraviolet screen for polyethylene and polypropylene, which is why black outdoor parts commonly outperform natural ones in sunlight, but it screens only the surface layer and does not replace the antioxidant package. No lifetime figure exists in our source library, so no specific service-life claim is made here.

What let-down ratio should I use for black masterbatch?#

The let-down ratio follows from the carbon black your part specifies divided by the carbon black in the concentrate: typical additions are 1-5 % of the base polymer, and PE pressure pipe needs 5.7-7.1 % (about 16.5:1 to 13:1) of a 35 wt% masterbatch to reach 2.0-2.5 wt%, above the 5-6.5 % (19:1 to 14:1) Ampacet publishes.

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Every figure on this page is checked against primary sources; see our methodology and fact-checking process.