View source for Chemistry:Carbon black

{{short description|Chemical compound}}
{{for multi|the climate forcing agent|Black carbon|the Carbon Black security company|Carbon Black (company)}}
{{Chembox
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| ImageFile = Carbon black.jpg
| ImageSize = 200px
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| IUPACName = 
| OtherNames = Acetylene black; Channel black; Furnace black; Lamp black; Thermal black; C.I. Pigment Black 6

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| Section1 = {{Chembox Identifiers
| CASNo = 1333-86-4
| CASNo_Ref = {{cascite|correct|CAS}}
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = 4XYU5U00C4
| PubChem = 
| EC_number = 215-609-9
| SMILES = C
  }}
| Section2 = {{Chembox Properties
| C=1
| Appearance = Black solid
| Density = 1.8–2.1{{nbsp}}g/cm<sup>3</sup> (20{{nbsp}}°C)<ref name=GESTIS>{{GESTIS|ZVG=91940}}</ref>
| MeltingPt = 
| BoilingPt = 
| Solubility = Practically insoluble<ref name=GESTIS/>
  }}
| Section3 = {{Chembox Hazards
| MainHazards = 
| FlashPt = 
| AutoignitionPt = 
| LD50 = > 15400{{nbsp}}mg/kg (oral rat)<ref name=GESTIS/><br>3000{{nbsp}}mg/kg (dermal, rabbit)<ref name=GESTIS/>
  }}
}}
[[File:Worker at carbon black plant2.jpg|thumb|Worker at carbon black plant, 1942]]
'''Carbon black''' (with subtypes '''acetylene black''', '''channel black''', '''furnace black''', '''lamp black''' and '''thermal black''') is a material produced by the [[Physics:Combustion#Incomplete|incomplete combustion]] of [[Chemistry:Coal tar|coal tar]], vegetable matter, or [[Chemistry:Petroleum|petroleum]] products, including fuel oil, [[Chemistry:Fluid catalytic cracking|fluid catalytic cracking]] tar, and [[Chemistry:Ethylene#Production|ethylene cracking]] in a limited supply of air. Carbon black is a form of [[Physics:Paracrystalline|paracrystalline]] [[Chemistry:Amorphous carbon|carbon]] that has a high [[Biology:Surface-area-to-volume ratio|surface-area-to-volume ratio]], albeit lower than that of [[Physics:Activated carbon|activated carbon]]. It is dissimilar to [[Earth:Soot|soot]] in its much higher surface-area-to-volume ratio and significantly lower (negligible and non-bioavailable) [[Astronomy:Polycyclic aromatic hydrocarbon|polycyclic aromatic hydrocarbon]] (PAH) content. However, carbon black can be used as a model compound for diesel soot to better understand how diesel soot behaves under various reaction conditions as carbon black and diesel soot have some similar properties such as particle sizes, densities, and copolymer adsorption abilities that contribute to them having similar behaviours under various reactions such as oxidation experiments.<ref>{{Cite journal |last1=Growney |first1=David J. |last2=Mykhaylyk |first2=Oleksandr O. |last3=Middlemiss |first3=Laurence |last4=Fielding |first4=Lee A. |last5=Derry |first5=Matthew J. |last6=Aragrag |first6=Najib |last7=Lamb |first7=Gordon D. |last8=Armes |first8=Steven P. |date=2015-09-29 |title=Is Carbon Black a Suitable Model Colloidal Substrate for Diesel Soot? |journal=Langmuir |language=en |volume=31 |issue=38 |pages=10358–10369 |doi=10.1021/acs.langmuir.5b02017 |pmid=26344920 |s2cid=206670654 |issn=0743-7463|doi-access=free }}</ref><ref>{{cite web|last=|first=|date=|title=Experimental and kinetic study of the interaction of a commercial soot toward NO at high temperature|url=http://www.combustion-institute.it/proceedings/MCS-7/papers/RKC/RKC-14.pdf|url-status=live|archive-url=https://web.archive.org/web/20130215105412/http://www.combustion-institute.it/proceedings/MCS-7/papers/RKC/RKC-14.pdf |archive-date=2013-02-15 |access-date=2012-04-25|website=}}</ref>{{Better source needed|date=January 2021}} Carbon black is used as a colorant and reinforcing [[Chemistry:Filler (materials)|filler]] in [[Engineering:Tire|tire]]s and other rubber products; pigment and wear protection additive in plastics, paints, and ink pigment.<ref>{{cite web |url=http://www.ceresana.com/en/market-studies/chemicals/carbon-black/ |title=Market Study: Carbon Black |publisher=Ceresana |access-date=2013-04-26}}</ref> It is used in the EU as a food colorant when produced from vegetable matter (E153).

The current [[Organization:International Agency for Research on Cancer|International Agency for Research on Cancer]] (IARC) evaluation is that, "Carbon black is possibly [[Biology:Carcinogen|carcinogen]]ic to humans ([[Chemistry:List of IARC Group 2B carcinogens|Group 2B]])".<ref name = "IARC">{{cite journal |journal= Views and Expert Opinions of an IARC/NORA Expert Group Meeting, Lyon, France, 30 June – 2 July 2009. IARC Technical Publication No. 42. Lyon, France: International Agency for Research on Cancer|year=2010 |volume=42 |pages=61–72 |title= Identification of Research Needs to Resolve the Carcinogenicity of High-priority IARC Carcinogens |author1=Kuempel, Eileen D.  |author2=Sorahan, Tom  |url=http://monographs.iarc.fr/ENG/Publications/techrep42/TR42-Full.pdf  |access-date=August 30, 2012 }}</ref> Short-term exposure to high concentrations of carbon black dust may produce discomfort to the upper respiratory tract through mechanical irritation.

==Common uses==
The most common use (70%) of carbon black is as a pigment and reinforcing phase in automobile tires. Carbon black also helps conduct heat away from the tread and belt area of the tire, reducing thermal damage and increasing tire life. Its low cost makes it a common addition to cathodes and anodes and is considered a safe replacement to lithium metal in lithium-ion batteries.<ref>{{Cite journal |last1=Gnanamuthu |first1=RM. |last2=Lee |first2=Chang Woo |date=2011-11-01 |title=Electrochemical properties of Super P carbon black as an anode active material for lithium-ion batteries |url=https://www.sciencedirect.com/science/article/pii/S0254058411007498 |journal=Materials Chemistry and Physics |language=en |volume=130 |issue=3 |pages=831–834 |doi=10.1016/j.matchemphys.2011.08.060 |issn=0254-0584}}</ref>  About 20% of world production goes into belts, hoses, and other non-tire rubber goods. The remaining 10% use of carbon black comes from pigment in inks, coatings, and plastics, as well as being used as a conductive additive in lithium-ion batteries.<ref name=":0">{{Cite journal |last1=Qi |first1=Xin |last2=Blizanac |first2=Berislav |last3=DuPasquier |first3=Aurelien |last4=Lal |first4=Archit |last5=Niehoff |first5=Philip |last6=Placke |first6=Tobias |last7=Oljaca |first7=Miodrag |last8=Li |first8=Jie |last9=Winter |first9=Martin |date=2015 |title=Influence of Thermal Treated Carbon Black Conductive Additive on the Performance of High Voltage Spinel Cr-Doped LiNi 0.5 Mn 1.5 O 4 Composite Cathode Electrode |url=https://iopscience.iop.org/article/10.1149/2.0401503jes |journal=Journal of the Electrochemical Society |language=en |volume=162 |issue=3 |pages=A339–A343 |doi=10.1149/2.0401503jes |issn=0013-4651}}</ref> 

Carbon black is added to [[Chemistry:Polypropylene|polypropylene]] because it absorbs [[Physics:Ultraviolet|ultraviolet]] radiation, which otherwise causes the material to degrade. Carbon black particles are also employed in some radar absorbent materials, in photocopier and laser printer [[Engineering:Toner|toner]], and in other inks and paints. The high tinting strength and stability of carbon black has also provided use in coloring of resins and films.<ref name="examples">{{cite web |url=http://www.carbonblack.jp/en/cb/youto.html |title=Application Examples of carbon black |publisher=Mitsubishi Chemical |access-date=2013-01-14}}</ref> Carbon black has been used in various applications for electronics. A good conductor of electricity, carbon black is used as a filler mixed in plastics, elastomer, films, adhesives, and paints.<ref name="examples" /> It is used as an antistatic additive agent in automobile fuel caps and pipes.

Carbon black from vegetable origin is used as a food coloring, known in Europe as additive '''E153'''. It is approved for use as additive '''153''' (Carbon blacks or Vegetable carbon) in Australia and New Zealand<ref name="standards">Australia New Zealand Food Standards Code{{cite web |url=http://www.comlaw.gov.au/Details/F2011C00827 |title=Standard 1.2.4 – Labelling of ingredients |access-date=2011-10-27}}</ref> but has been banned in the US.<ref>US FDA:{{cite web |url=https://www.fda.gov/ForIndustry/ColorAdditives/ColorAdditiveInventories/ucm106626.htm |title=Color Additive Status List |website=[[Organization:Food and Drug Administration|Food and Drug Administration]] |access-date=2011-10-27}}</ref> The color pigment carbon black has been widely used for many years in food and beverage packaging. It is used in multi-layer UHT milk bottles in the US, parts of Europe and Asia, and South Africa, and in items like microwavable meal trays and meat trays in New Zealand.

The Canadian Government's extensive review of carbon black in 2011 concluded that carbon black could continue to be used in products – including food packaging for consumers – in Canada. This was because "in most consumer products carbon black is bound in a matrix and unavailable for exposure, for example as a pigment in plastics and rubbers" and "it is proposed that carbon black is not entering the environment in a quantity or concentrations or under conditions that constitute or may constitute a danger in Canada to human life or health."<ref>{{cite web |url=http://www.ec.gc.ca/ese-ees/default.asp?lang=en&n=2cf34283-1 |title=Draft Screening Assessment for the Challenge |date=29 January 2010 | access-date=2013-01-14}}</ref>

Within Australasia, the color pigment carbon black in packaging must comply with the requirements of either the EU or US packaging regulations. If any colorant is used, it must meet European partial agreement AP(89)1.<ref>{{cite web |url=http://www.foodstandards.govt.nz/foodstandards/foodstandardscode.cfm |title=Australia New Zealand Food Standards Code |access-date=2013-01-14 |archive-url=https://web.archive.org/web/20121220061636/http://www.foodstandards.govt.nz/foodstandards/foodstandardscode.cfm |archive-date=2012-12-20 |url-status=dead }}</ref>

Total production was around {{convert|8100000|MT|ST}} in 2006.<ref>{{cite web|title=What is carbon black|url=http://www.carbon-black.org/what_is.html|url-status=dead|archive-url=https://web.archive.org/web/20090401121937/http://www.carbon-black.org/what_is.html#|archive-date=2009-04-01|access-date=2009-04-14|publisher=International carbon black Association}}</ref> Global consumption of carbon black, estimated at 13.2 million metric tons, valued at US$13.7 billion, in 2015, is expected to reach 13.9 million metric tons, valued at US$14.4 billion in 2016.

Global consumption is forecast to maintain a CAGR (compound annual growth rate) of 5.6% between 2016 and 2022, reaching 19.2 million metric tons, valued at US$20.4 billion, by 2022.<ref>Carbon Black - A Global Market Overview Jan 2016 • Industry Experts Report CP024 • 328 pages</ref>

==Reinforcing carbon blacks==
The highest volume use of carbon black is as a reinforcing filler in rubber products, especially tires. While a pure [[Chemistry:Vulcanization|gum vulcanization]] of [[Chemistry:Styrene-butadiene|styrene-butadiene]] has a [[Physics:Tensile strength|tensile strength]] of no more than 2 MPa and negligible abrasion resistance, compounding it with 50% carbon black by weight improves its tensile strength and wear resistance as shown in the table below. It is used often in the aerospace industry in elastomers for aircraft vibration control components such as engine mounts.

{| class="wikitable"
|+Certain types of carbon black used in tires, plastics and paints
|-
!Name	
!Abbrev.
!ASTM <br> desig.	
!Particle<br> Size <br> nm	
!Tensile <br>strength <br> MPa	
!Relative<br> laboratory<br> abrasion	
!Relative <br> roadwear<br> abrasion
|-
|Super Abrasion Furnace	|| align=center|SAF	|| align=center|N110	|| align=center|20–25	||align=center|25.2	||align=center|1.35	||align=center|1.25
|-
|Intermediate SAF	||align=center|ISAF		||align=center|N220		||align=center|24–33		||align=center|23.1		||align=center|1.25		||align=center|1.15
|-
| High Abrasion Furnace	||align=center|HAF	||align=center|N330	||align=center|28–36	||align=center|22.4	||align=center|1.00	||align=center|1.00
|-
| Easy Processing Channel	||align=center|EPC	||align=center|N300	||align=center|30–35	||align=center|21.7	||align=center|0.80	||align=center|0.90
|-
| Fast Extruding Furnace	||align=center|FEF	||align=center|N550	||align=center|39–55	||align=center|18.2	||align=center|0.64	||align=center|0.72 
|-
| High Modulus Furnace	||align=center|HMF	||align=center|N660	||align=center|49–73	||align=center|16.1	||align=center|0.56	||align=center|0.66
|-
| Semi-Reinforcing Furnace	||align=center|SRF	||align=center|N770	||align=center|70–96	||align=center|14.7	||align=center|0.48	||align=center|0.60
|-
| Fine Thermal	||align=center|FT	||align=center|N880	||align=center|180–200	||align=center|12.6	||align=center|0.22	||align=center|–
|-
| Medium Thermal	||align=center|MT	||align=center|N990	||align=center|250–350	||align=center|9.8	||align=center|0.18	||align=center|–
|-
|}

Practically all rubber products where tensile and abrasion wear properties are important use carbon black, so they are black in color. Where physical properties are important but colors other than black are desired, such as white tennis shoes, precipitated or [[Chemistry:Fumed silica|fumed silica]] has been substituted for carbon black. Silica-based fillers are also gaining market share in automotive tires because they provide better trade-off for [[Physics:Fuel efficiency|fuel efficiency]] and wet handling due to a lower rolling loss. Traditionally silica fillers had worse abrasion wear properties, but the technology has gradually improved to a point where they can match carbon black abrasion performance.

==Pigment==
Carbon black (Color Index International, PBK-7) is the name of a common black pigment, traditionally produced from charring organic materials such as wood or bone. It appears black because it reflects very little light in the visible part of the spectrum, with an [[Earth:Albedo|albedo]] near zero. The actual albedo varies depending on the source material and method of production. It is known by a variety of names, each of which reflects a traditional method for producing carbon black:
* '''Ivory black''' was traditionally produced by charring ivory or bones (see bone char).
* '''Vine black''' was traditionally produced by charring [[Earth:Desiccation#Biology and ecology|desiccated]] grape vines and stems.
* '''Lamp black''' was traditionally produced by collecting soot from oil lamps.

All of these types of carbon black were used extensively as paint pigments since prehistoric times.<ref>Winter, J. and West FitzHugh, E., Pigments based on Carbon, in Berrie, B.H. Editor, Artists’ Pigments, A Handbook of Their History and Characteristics, Volume 4, pp. 1–37.</ref> Rembrandt, Vermeer, Van Dyck, and more recently, Cézanne, Picasso and Manet<ref>[http://colourlex.com/project/bone-black/ Bone black], ColourLex</ref> employed carbon black pigments in their paintings. A typical example is Manet's "Music in the Tuileries",<ref>Bomford D, Kirby J, Leighton, J., Roy A. Art in the Making: Impressionism.  National Gallery Publications, London, 1990, pp. 112–119.</ref> where the black dresses and the men's hats are painted in ivory black.<ref>[http://colourlex.com/project/manet-music-in-the-tuileries/ Édouard Manet, 'Music in the Tuileries Gardens'], ColourLex</ref>

Newer methods of producing carbon black have largely superseded these traditional sources. For artisanal purposes, carbon black produced by any means remains common.<ref name="examples"/>

== Surface and surface chemistry ==
All carbon blacks have [[Physics:Chemisorption|chemisorbed]] oxygen complexes (i.e., carboxylic, [[Chemistry:Quinone|quinonic]], lactonic, [[Chemistry:Phenols|phenolic]] groups and others) on their surfaces to varying degrees depending on the conditions of manufacture.<ref>{{cite journal |last1=Hennion |first1=Marie-Claire |title=Graphitized carbons for solid-phase extraction |journal=Journal of Chromatography A |date=July 2000 |volume=885 |issue=1–2 |pages=73–95 |doi=10.1016/S0021-9673(00)00085-6|pmid=10941668 }}</ref> These surface oxygen groups are collectively referred to as volatile content. It is also known to be a non-conductive material due to its volatile content.

The coatings and inks industries prefer grades of carbon black that are acid-oxidized. Acid is sprayed in high-temperature dryers during the manufacturing process to change the inherent surface chemistry of the black. The amount of chemically-bonded oxygen on the surface area of the black is increased to enhance performance characteristics.

== Use in lithium-ion batteries ==
[[File:Carbon_Black_Structure.png|thumb|The generic structure of carbon black.]]
Carbon black is a common conductive additive for lithium ion batteries as they have small particle sizes and large [[Physics:Specific surface area|specific surface areas]] (SSA) which allow for the additive to be well distributed throughout the cathode or anode in addition to being cheap and long-lasting.<ref name=":0" /><ref name=":1">{{Cite journal |last1=Hu |first1=Jingwei |last2=Zhong |first2=Shengwen |last3=Yan |first3=Tingting |date=2021-10-01 |title=Using carbon black to facilitate fast charging in lithium-ion batteries |url=https://www.sciencedirect.com/science/article/pii/S0378775321008545 |journal=Journal of Power Sources |language=en |volume=508 |pages=230342 |doi=10.1016/j.jpowsour.2021.230342 |bibcode=2021JPS...50830342H |issn=0378-7753}}</ref> Unlike [[Chemistry:Graphite#Batteries|graphite]], which is one of the other common materials used in chargeable batteries, carbon black consists of crystal lattices that are further apart and promotes Li<sup>+</sup> [[Chemistry:Intercalation|intercalation]] because it allows more pathways for lithium storage.<ref name=":1" />

Carbon black has a low density that allows for a large volume of it to be dispersed so that its conductive effects are applied evenly throughout the battery.<ref>{{Cite journal |last1=Younesi |first1=Reza |last2=Christiansen |first2=Ane Sælland |last3=Scipioni |first3=Roberto |last4=Ngo |first4=Duc-The |last5=Simonsen |first5=Søren Bredmose |last6=Edström |first6=Kristina |last7=Hjelm |first7=Johan |last8=Norby |first8=Poul |date=2015 |title=Analysis of the Interphase on Carbon Black Formed in High Voltage Batteries |url=https://doi.org/10.1149/2.0761507jes |journal=Journal of the Electrochemical Society |language=en |volume=162 |issue=7 |pages=A1289–A1296 |doi=10.1149/2.0761507jes |s2cid=53486824 |issn=0013-4651|doi-access=free }}</ref><ref>{{Cite journal |last1=Dominko |first1=Robert |last2=Gaberscek |first2=Miran |last3=Drofenik |first3=Jernej |last4=Bele |first4=Marjan |last5=Pejovnik |first5=Stane |last6=Jamnik |first6=Janko |date=2003-06-01 |title=The role of carbon black distribution in cathodes for Li ion batteries |url=https://www.sciencedirect.com/science/article/pii/S0378775303002507 |journal=Journal of Power Sources |series=Selected papers presented at the 11th International Meeting on Lithium Batteries |language=en |volume=119-121 |pages=770–773 |doi=10.1016/S0378-7753(03)00250-7 |bibcode=2003JPS...119..770D |issn=0378-7753}}</ref> Furthermore, its arrangement of randomly distributed graphite-like crystals improves battery stability because of the decrease in the potential barrier of lithium intercalation into graphite, which ultimately affects the performance of cathodes.<ref name=":1" />

While carbon black is lightweight and well dispersed throughout the battery and increases the conductive performance of batteries, it also contains oxygen containing hydrophilic functional groups that can cause side reactions to occur in the battery and lead to the decomposition of electrolyte. [[Physics:Graphitization|Graphitization]] (heating) of carbon black can thermally decompose the hydrophilic functional groups and thus increase the cycle life of the battery which maintains the conductive abilities of carbon black while mitigating the damage that can be caused to batteries by  hydrophilic functional groups. 

Half cells created with heavy graphitization, light graphitization, and no graphitization showed that the cell created with heavy graphitization had a stable cycle life of 320 cycles, the cell with light graphitization showed a stable cycle life of 200 cycles, and the cell with no graphitization showed a stable cycle life of 160 cycles.<ref name=":0" />

== Safety ==
===Carcinogenicity===
Carbon black is considered ''possibly carcinogenic to humans'' and classified as a Group 2B carcinogen because there is sufficient evidence in experimental animals with inadequate evidence in human [[Social:Epidemiology|epidemiological studies]].<ref name="IARC"/> The evidence of carcinogenicity in animal studies comes from two chronic inhalation studies and two [[Biology:Intratracheal instillation|intratracheal instillation]] studies in rats, which showed significantly elevated rates of lung cancer in exposed animals.<ref name="IARC"/> An inhalation study on mice did not show significantly elevated rates of lung cancer in exposed animals.<ref name="IARC"/> Epidemiologic data comes from three cohort studies of carbon black production workers. Two studies, from the United Kingdom and Germany, with over 1,000 workers in each study group showed elevated mortality from lung cancer.<ref name="IARC"/> A third study of over 5,000 carbon black workers in the United States did not show elevated mortality.<ref name="IARC"/> Newer findings of increased lung cancer mortality in an update from the UK study suggest that carbon black could be a [[Medicine:Cancer staging|late-stage carcinogen]].<ref name = "sorahan">{{cite journal|vauthors=Sorahan T, Harrington JM |title=A "lugged" analysis of lung cancer risks in UK carbon black production workers, 1951–2004|journal=Am J Ind Med|volume=50|issue=8|pages=555–564|year=2007|pmid=17516558|doi=10.1002/ajim.20481}}</ref><ref name = "ward">{{cite journal |vauthors=Ward EM, Schulte PA, Straif K, Hopf NB, Caldwell JC, Carreón T, DeMarini DM, Fowler BA, Goldstein BD, Hemminki K, Hines CJ, Pursiainen KH, Kuempel E, Lewtas J, Lunn RM, Lynge E, McElvenny DM, Muhle H, Nakajima T, Robertson LW, Rothman N, Ruder AM, Schubauer-Berigan MK, Siemiatycki J, Silverman D, Smith MT, Sorahan T, Steenland K, Stevens RG, Vineis P, Zahm SH, Zeise L, Cogliano VJ |title=Research recommendations for selected IARC-classified agents |journal=Environmental Health Perspectives |volume=118 |issue=10 |pages=1355–62 |year=2010|pmid=20562050 |doi=10.1289/ehp.0901828 |pmc=2957912}}</ref> However, a more recent and larger study from Germany did not confirm this hypothesis.<ref name = "morfeld">{{cite journal|vauthors=Morfeld P, McCunney RJ |title=Carbon black and lung cancer: Testing a new exposure metric in a German cohort|journal=Am J Ind Med|volume=50|issue=8|pages=565–567|year=2007|pmid=17620319|doi=10.1002/ajim.20491}}</ref>

=== Occupational safety ===
There are strict guidelines available and in place to ensure employees who manufacture carbon black are not at risk of inhaling unsafe doses of carbon black in its raw form.<ref>{{cite web|url=https://www.cdc.gov/niosh/docs/81-123/pdfs/0102.pdf|title=Occupational Safety and Health Guidelines for carbon black: Potential Human Carcinogen, Centres of Disease Control and Prevention, National Institute for Occupational Safety and Health|access-date=2013-01-14}}</ref> Respiratory [[Social:Personal protective equipment|personal protective equipment]] is recommended to properly protect workers from inhalation of carbon black. The recommended type of respiratory protection varies depending on the concentration of carbon black used.<ref name = guideline>{{cite web |url=https://www.cdc.gov/niosh/docs/81-123/pdfs/0102.pdf |title=Occupational Safety and Health Guideline for Carbon Black: Potential Human Carcinogen |publisher=Centers of Disease Control and Prevention, National Institute for Occupational Safety and Health |access-date=11 January 2013}}</ref>

People can be exposed to carbon black in the workplace by inhalation and contact with the skin or eyes. The [[Organization:Occupational Safety and Health Administration|Occupational Safety and Health Administration]] (OSHA) has set the legal limit ([[Earth:Permissible exposure limit|Permissible exposure limit]]) for carbon black exposure in the workplace at 3.5&nbsp;mg/m<sup>3</sup> over an 8-hour workday. The [[Organization:National Institute for Occupational Safety and Health|National Institute for Occupational Safety and Health]] (NIOSH) has set a [[Earth:Recommended exposure limit|Recommended exposure limit]] (REL) of 3.5&nbsp;mg/m<sup>3</sup> over an 8-hour workday. At levels of 1750&nbsp;mg/m<sup>3</sup>, carbon black is immediately dangerous to life and health.<ref>{{Cite web|title = CDC – NIOSH Pocket Guide to Chemical Hazards – Carbon black|url = https://www.cdc.gov/niosh/npg/npgd0102.html|website = www.cdc.gov|access-date = 2015-11-27}}</ref>

== See also ==
{{Div col}}
* [[Physics:Activated carbon|Activated carbon]]
* [[Earth:Biochar|Biochar]]
* George Oenslager - early use of carbon black in rubber
* [[Chemistry:Heavy metals|Heavy metals]]
* Jean-Baptiste Donnet - carbon black pioneer
* Joseph C. Krejci - carbon black pioneer
* [[Chemistry:Kværner process|Kværner process]] - production from hydrocarbons
* [[Chemistry:List of inorganic pigments|List of inorganic pigments]]
* Siegfried Wolff - carbon black pioneer
* William B. Wiegand - carbon black pioneer
{{Div col end}}

== References ==
{{reflist|30em}}

==Further reading==
{{refbegin}}
* Doerner, Max. ''The Materials of the Artist and Their Use in Painting: With Notes on the Techniques of the Old Masters'', Revised Edition. Harcourt (1984). {{ISBN|0-15-657716-X}}. This is a contemporary [[Social:English language|English language]] edition of a work originally published in [[Social:German language|German]].
* Meyer, Ralph. ''The Artist's Handbook of Materials and Techniques''. Fifth Edition, Revised and Updated. Viking (1991) {{ISBN|0-670-83701-6}}
* [https://web.archive.org/web/20070820050437/http://www.carbon-black.org/user_guide.html Carbon Black: A users guide]. Published by the International Carbon Black Association.
{{refend}}

== External links ==
{{Americana Poster|Blacks|Carbon black}}
* {{ICSC|0471|04}}
* [https://www.cdc.gov/niosh/npg/npgd0102.html "Carbon black"] – ''NIOSH Pocket Guide to Chemical Hazards'', CDC website entry
* [https://tshaonline.org/handbook/online/articles/doc01 "Carbon Black Industry"] from the ''[[Handbook of Texas]] Online''
* [http://carbon-black.org International Carbon Black Association]
*  [https://pentacarbon.de/en/special-carbon-blacks/ Special Carbon Blacks - PentaCarbon GmbH]

{{Allotropes of carbon}}

[[Category:Carbon]]
[[Category:E-number additives]]
[[Category:Elastomers]]
[[Category:IARC Group 2B carcinogens]]
[[Category:Inorganic pigments]]
[[Category:Rubber properties]]

{{Sourceattribution|Carbon black}}