Why does carbon black require post-treatment?
The purpose of post-treatment of oxidized carbon black is to change its surface chemical properties. For pigment carbon black, in order to form a stable colloidal dispersion in paint or ink systems, it is necessary to improve the dispersibility of the carbon black pigment in polar solvents. Therefore, it is necessary to introduce oxygen-containing functional groups on the surface of carbon black to make the surface more polar, which is called surface modification.
Methods of post-treatment of carbon black oxidation
There are many methods for surface modification and oxidation post-treatment of carbon black, such as hot air oxidation method, nitric acid oxidation method, ozone oxidation method, peroxide oxidation method, and low-temperature plasma oxidation method.
Advantages of post-treatment of carbon black oxidation
The purpose of post-treatment of carbon black oxidation is to change the functional groups on the surface of carbon black. The pH index of carbon black is determined by the acidity and basicity of the functional groups on the surface of carbon black. Different functional groups on the surface of carbon black can react with different substrates, which is more conducive to the dispersion and combination of carbon black with substrates. In fact, even without oxidation treatment, carbon black needs to be processed before adding to substrates for better dispersion. After oxidation treatment, carbon black not only has the advantage of easy dispersion but also improves the viscosity, stability, and flowability of carbon black, making it better combined with substrates, which results in cost savings and no discoloration or fading.