Carbon Black

Carbon blacks are typically elemental Carbon that is available in highly dispersed powdered forms. They are produced from hydrocarbons by controlled vapour-phase pyrolysis.

Carbon Black is one of the most important types of pigments that have major industrial applications. In Producing Carbon Black there are numerous processes available. Mostly all the production processes depends on thermal decomposition or incomplete burning of fuel oil or natural gas (hydro carbons). Majority of all carbon black is made by employing the furnace process. "Furnace black" and "channel black" are the two very popular variants of Carbon Black. Others include acetylene black, lamp black and thermal black. Mostly all types of Carbon blacks contain oxygen, hydrogen, nitrogen and sulphur.

Characteristics of Carbon Black

• Average particle diameter: In most of the commercially-produced carbon blacks the range is from 0.01 to 0.4 micrometres (µm)
• Average aggregate diameters: Ranges from 0.1- 0.8µm
• Percentage of Elemental Carbon: Between 97 to 99
• Particle size: The following graph shows the particle size of some carbon black pigments.

• Channel Black
• Furnace Black
• Acetylene Black
• Lamp Black
• Blacking

• High color strength in mass tone and in toned down applications.
• Excellent UV protecting properties
• Shows good chemical inertness
• Good surface appearance
• Outstanding antistatic properties

The requirements of applicability of Carbon Black are critical, their importance also vary according to application. Few such requirements are discussed here:

Color Strength- Colour strength of a few type of carbon Black pigment as appearing in Acrylonitrile butadiene styrene (ABS) polymer is shown in the graph.

Masterbatch Dilutability- Masterbatch dilutability is approximated and compared by the process of measuring the melt viscosity of a given masterbatch formulation. In fact masterbatch dilutability is critical. In the selection of the right carbon black and can result in saving substantial formulation cost.

UV Stability- By addition of carbon black, the stability with regard to UV rays can be increased.

Carbon Black Dispersability

Blue Tone

Carbon black is widely used into many horizons. This include other than pigmenting, applications like UV stabilizing and as a conductive agent in a vast number of specialty products.

Popular applications include:
Thermoplastic moulding- Some of the significant applications of carbon black are shown here. Prominent application is found in automotive applications.

(Steering and Dash Board system of a car using Carbon Black Pigment)

Toners and Printing Inks- Carbon black enhance formulations and offer broad flexibility in terms of specific color requirements. Applications of carbon Blacks include Letterpress, Lithographic, gravure, flexographic, and screen printing processes. It is important here to know that each of these processes needs different performance attributes.

Plastics- Used in plastic masterbatch applications, like films, conductive packaging, pipes, fibers, moldings, and semi-conductive cable compounds.

Flexography ink- This ink is fluid, with instant drying features. Rheology is a vital factor here. Carbon Black pigments with low oil adsorption pigments are a must.

Offset printing- A high color strength along with high pigment loadings, smooth flow, and a viscosity that is fairly working are needed from the application of Carbon Black. Offset ink must not be miscible with water. If the requirement is high gloss then lower oil absorption pigments are required.

Coatings- Carbon blacks provide coating applications for sectors like marine and aerospace. By way of pigmentation, conductivity and UV protection.

Screen Printing- The critical performance factors are rheology, low viscosity. This can be achieved by pigment blacks that has higher structures. Optical density property can be obtained by relatively low pigment black loadings.

Industrial Rubber Products and Tyres- Carbon black is applied for uses like innerliners for tyres, sidewalls and treads, for industrial rubber products, usages include belts, hoses and gaskets. In fact a majority of the Carbon Black that is produced goes into the making of reinforcing filler for use in tyres and other rubber article.

Carbon Black exposure can be hazardous in some cases. Typical classes of chemicals with carcinogenic nature like polycyclic aromatic hydrocarbons (PAHs), sulphur-containing PAHs, nitro derivatives of PAHs are adsorbed on to surface of carbon black.