What is Carbon Black?
Carbon black is a black special chemical that is available as powder or beads. It is manufactured through highly controlled processes and contains more than 95 percent pure carbon and other components including oxygen, hydrogen and nitrogen. The black particles are 10 nm to approx. 500 nm big and fuse into chain-like aggregates that define the structure of individual carbon black grades. Depending on the production process, carbon black types differ in size, surface chemistry, porosity and many other characteristics. During the aftertreatment process, the oxygen percentage within the carbon black can be changed according to the required needs.
Carbon black is used in a multitude of industries. By enhancing the physical, electrical and optical properties of various materials, carbon black brings the final product to the top of its performance. It can be blended with additives, elastomers or binding agents and integrated into the customers' existing formulas, or it can be pre-processed in a form called "preparation". Preparation is a mixture of carbon black and other additives and streamlines production .
The properties of most carbon black grades are determined by industry-wide standards developed by the German Institute for Standardization (DIN), the International Organization for Standardization (ISO) and the American Society for Testing and Materials (ASTM). These standards are not only used as a measure by which types of carbon black are characterized, but also as a quality assurance tool for the production process.
How Carbon Black Types Differ
Several chemical and physical properties serve to determine the differences between carbon black varieties. Aggregation, or structuring, refers to the way in which the carbon particles are permanently fused together in a random branching structure, or chain, and impacts rheology reinforcement as well as light scattering properties. Particle size is another criterion used to distinguish carbon black types. Small particles lead to a very high tinting strength, high jetness level, excellent UV-protection and better conductivity. Big particles improve the viscosity and dispersibility properties within the application. Another parameter is the structure of these aggregates. The primary particles can either be bond loosely together or piled up in a very complex construct. A high structure—specifically a complex system— leads to a very strong reinforcement power of carbon black, while a low structure achieves positive results in the gloss of coatings and inks. The third main criterion to distinguish carbon black types is the chemical characteristics of the particle surface, which can either be acidic or basic depending on the type of volatile components on the surface. Acidic volatile components improve the dispersibility of carbon black and is why our after-treatment processing has been designed to further enhance the performance of our products and adapt it to customers’ needs.
Like these and other defining aspects, the purity level on the surface of the carbon black and the particle distribution depend on the production process. Purity refers to the quantities of other substances which are incorporated into the carbon black aside from pure carbon, including nitrogen, hydrogen and oxygen.