CI 77266, also known as Carbon black, is chemically classified as an inorganic colorant. This pigment is composed of finely divided particles of elemental carbon obtained by the incomplete combustion of hydrocarbons. It is widely used in various industrial and cosmetic applications.
Chemical Composition and Structure
CI 77266 is an inorganic compound primarily composed of elemental carbon (C). The particles of carbon black are formed through the process of incomplete combustion or thermal decomposition of hydrocarbons, resulting in extremely fine particles that provide a deep black pigment.
Physical Properties
This pigment typically appears as an extremely fine black powder. It has a high surface area and strong tinting strength, offering excellent covering power. CI 77266 is known for its exceptional resistance to light and heat, making it suitable for long-lasting applications. Its high stability and non-reactivity contribute to its versatility.
Chemical Industrial Synthesis Process
- Preparation of reagents. The main raw materials include liquid or gaseous hydrocarbons such as coal tar oil, natural gas, or mineral oil.
- Incomplete combustion. The production of CI 77266 begins with the incomplete combustion of hydrocarbons. This combustion is carried out in a controlled environment where the amount of oxygen is limited, allowing the formation of finely divided carbon particles.
- Cooling. The gas containing the carbon particles is rapidly cooled to stop further combustion reactions.
- Collection. The carbon particles are collected using filters, cyclones, or electrostatic precipitators.
- Washing and purification. The collected particles are washed with water and, if necessary, treated with acids to remove impurities such as ash or metals.
- Drying. The purified carbon particles are dried at controlled temperatures to remove residual moisture.
- Grinding. The dried carbon black is ground to obtain a fine and uniform powder.
- Classification. The ground powder is classified to ensure a uniform particle size using sieves or air classifiers.
- Stabilization. The CI 77266 powder is stabilized to ensure its stability during transportation and storage, preventing aggregation and degradation.
- Quality control. The CI 77266 undergoes rigorous quality testing to ensure it meets standards for purity, color intensity, and safety. These tests include chemical analysis, spectroscopy, and physical tests to determine particle size and rheological properties.
What it is used for and where
Cosmetics
Restricted cosmetic ingredient as IV/126 a Relevant Item in the Annexes of the European Cosmetics Regulation 1223/2009. Ingredients reported:
- Carbon black. Wording of conditions of use and warnings. Purity > 97 %, with the following impurity profile: Ash content ≤ 0,15 %, total sulphur ≤ 0,65 %, total PAH ≤ 500 ppb and benzo(a)pyrene ≤ 5 ppb, dibenz(a,h)anthracene ≤ 5 ppb, total As ≤ 3 ppm, total Pb ≤ 10 ppm, total Hg ≤ 1 ppm.
- Carbon black (nano). Maximum concentration in ready for use preparation 10%. Wording of conditions of use and warnings Not to be used in applications that may lead to exposure of the end user's lungs by inhalation. Only nanomaterials having the following characteristics are allowed: — Purity > 97 %, with the following impurity profile: Ash content ≤ 0,15 %, total sulphur ≤ 0,65 %, total PAH ≤ 500 ppb and benzo(a)pyrene ≤ 5 ppb, dibenz(a,h)anthracene ≤ 5 ppb, total As ≤ 3 ppm, total Pb ≤ 10 ppm, and total Hg ≤ 1 ppm; — Primary particle size ≥ 20 nm.’
Cosmetics - INCI Functions
Colorant. This ingredient has the function of colouring the solution in which it is inserted in a temporary, semi-permanent or permanent manner, either alone or in the presence of the complementary components added for colouring.
CI 77266 is widely used in cosmetic products such as eyeliners, mascaras, eyeshadows, and lipsticks due to its intense black color and high opacity.
Industrial Applications
Paints and Coatings: In the paint industry, carbon black is used to achieve deep black shades and enhance UV resistance. Its stability and strong tinting properties make it ideal for both decorative and protective coatings.
Plastics and Polymers: This pigment is employed in the production of plastics and polymers to improve color uniformity, opacity, and UV resistance. It is commonly used in products like automotive parts, packaging materials, and consumer goods.
Inks: CI 77266 is extensively used in printing inks for its high color strength and permanence. It ensures sharp, dark prints and is used in various types of inks including those for newspapers, magazines, and packaging.
Rubber: In the rubber industry, carbon black is a crucial component in the manufacturing of tires and other rubber products. It enhances the durability, strength, and wear resistance of rubber materials.
Safety
Many scientific studies have examined the Carbon black and the actions that this chemical compound derived from coal puts in place in the human body and have found that this chemical compound acts as a weak genotoxic agent (1) and can, in the form of nanoparticles, accelerate the development of lung cancer (2).
Other studies believe that Carbon black "should" not be considered a direct genotoxic (3).
Considering the mixed results of the numerous scientific studies, it remains, in my opinion, a danger that is difficult to overcome and, since it is about health, I exclude this ingredient from my positive choices.
