Carbon black

Carbon black (subtypes are acetylene black, channel black, furnace black, lamp black and thermal black) is a material produced by the incomplete combustion of heavy petroleum products such as FCC tar, coal tar, or ethylene cracking tar. Carbon black is a form of paracrystalline carbon that has a high surface-area-to-volume ratio, albeit lower than that of activated carbon. It is dissimilar to soot in its much higher surface-area-to-volume ratio and significantly lower (negligible and non-bioavailable) polycyclic aromatic hydrocarbon (PAH) content. However, carbon black is widely used as a model compound for diesel soot for diesel oxidation experiments. Carbon black is mainly used as a reinforcing filler in tires and other rubber products. In plastics, paints, and inks, carbon black is used as a color pigment. Carbon black (subtypes are acetylene black, channel black, furnace black, lamp black and thermal black) is a material produced by the incomplete combustion of heavy petroleum products such as FCC tar, coal tar, or ethylene cracking tar. Carbon black is a form of paracrystalline carbon that has a high surface-area-to-volume ratio, albeit lower than that of activated carbon. It is dissimilar to soot in its much higher surface-area-to-volume ratio and significantly lower (negligible and non-bioavailable) polycyclic aromatic hydrocarbon (PAH) content. However, carbon black is widely used as a model compound for diesel soot for diesel oxidation experiments. Carbon black is mainly used as a reinforcing filler in tires and other rubber products. In plastics, paints, and inks, carbon black is used as a color pigment. The current International Agency for Research on Cancer (IARC) evaluation is that, 'Carbon black is possibly carcinogenic to humans (Group 2B)'. Short-term exposure to high concentrations of carbon black dust may produce discomfort to the upper respiratory tract, through mechanical irritation. Total production was around 8,100,000 metric tons (8,900,000 short tons) in 2006. 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. 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. About 20% of world production goes into belts, hoses, and other non-tire rubber goods. The balance is mainly used as a pigment in inks, coatings and plastics. For example, it is added to polypropylene because it absorbs 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 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. 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. 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 but has been banned in the US. 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 should 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.” 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. The highest volume use of carbon black is as a reinforcing filler in rubber products, especially tires. While a pure gum vulcanization of styrene-butadiene has a 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. 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 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 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. 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 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: