Article last updated: October 15, 2024
Hc Red No. 9, also known by its chemical name [6-[[3-chloro-4-(methylamino)phenyl]imino]-4-methyl-3-oxocyclohexa-1,4-dien-1-yl]urea, is a synthetic dye primarily used in hair dyeing products. This vibrant red dye is a member of the azo dye family, which is known for its vivid colors and stability. Its unique chemical structure allows it to impart a rich, long-lasting red hue to hair, making it a popular choice in the cosmetic industry.
The history of Hc Red No. 9 in cosmetics dates back to the mid-20th century when synthetic dyes began to replace natural dyes due to their superior performance and consistency. Over the years, it has been refined and tested extensively to ensure its safety and effectiveness in hair dye formulations. Its adoption in the beauty industry was driven by the demand for more reliable and vibrant hair coloring options.
The production of Hc Red No. 9 involves a series of chemical reactions starting with the synthesis of the core azo compound. This process typically includes the diazotization of an aromatic amine, followed by coupling with a suitable coupling component to form the azo linkage. The resulting compound is then further modified to achieve the desired color properties and stability. The final product is a fine powder that can be easily incorporated into various hair dye formulations.
In this section, we will delve into the officially recognized cosmetic benefits and uses of Hc Red No. 9:
Hc Red No. 9 is primarily used as a hair dye. This means that its main function is to impart color to the hair. When included in hair dye formulations, it helps achieve a specific shade of red, adding vibrancy and depth to the hair color. This can be particularly beneficial for those looking to enhance their natural hair color or completely change it to a striking red hue. The ingredient works by penetrating the hair shaft and depositing color, ensuring that the dye is long-lasting and resistant to washing out quickly.
Note: the listed benefits above are exclusively based on the officially recognized and defined functions of the ingredient, as documented by the International Nomenclature of Cosmetic Ingredients (INCI).
Hc Red No. 9, like many cosmetic ingredients, comes with its own set of considerations regarding safety, suitability, and allergenic potential. While it is primarily used for hair dyeing, it is essential to be aware of the possible side effects associated with its topical application:
Regarding individuals who are pregnant or breastfeeding, data and research on the topical usage of Hc Red No. 9 during pregnancy are lacking. Therefore, it is advisable for these individuals to consult a healthcare professional for further advice before using products containing this ingredient.
The occurrence of side effects or adverse reactions from Hc Red No. 9 is relatively uncommon, but it is always prudent to perform a patch test before widespread usage to ensure personal tolerance.
In terms of comedogenicity, Hc Red No. 9 has a rating of 0, meaning it is considered non-comedogenic. This is good news for individuals prone to acne, blemishes, or breakouts, as it is unlikely to clog pores or exacerbate skin issues.
