Article last updated: October 15, 2024
Hc Yellow No. 7, also known by its chemical name 1-(4-Aminophenylazo)-2-methyl-4-bis(.beta.-hydroxyethyl)aminobenzene, is a synthetic dye used primarily in hair dyeing products. This vibrant yellow compound is part of the azo dye family, which is characterized by the presence of a nitrogen-nitrogen double bond (N=N) linking two aromatic rings. In the world of cosmetics, it is valued for its ability to impart a bright, long-lasting yellow hue to hair.
The history of Hc Yellow No. 7 in cosmetics dates back to the mid-20th century when synthetic dyes began to replace natural dyes due to their superior stability and color consistency. Over the years, it has become a staple in the formulation of various hair dye products, thanks to its effectiveness and reliability.
The production of Hc Yellow No. 7 involves a multi-step chemical synthesis process. It starts with the nitration of aniline to produce nitroaniline, which is then reduced to form phenylenediamine. This intermediate undergoes diazotization, where it is treated with nitrous acid to form a diazonium salt. The final step involves coupling this diazonium compound with another aromatic amine to produce the vibrant yellow azo dye. This meticulous process ensures the purity and consistency of the dye, making it suitable for use in cosmetic formulations.
In this section, we will delve into the officially recognized cosmetic benefits and uses of Hc Yellow No. 7:
Hc Yellow No. 7 is primarily used as a hair dye. This means that its main function is to impart color to the hair. Whether you’re looking to add a vibrant yellow hue or create a specific shade by mixing it with other colors, Hc Yellow No. 7 is a key ingredient in achieving the desired hair color. It works by penetrating the hair shaft and depositing color, which can be semi-permanent or permanent depending on the formulation. This makes it a valuable component in various hair dye products, from at-home kits to professional salon treatments.
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 Yellow No. 7, like many cosmetic ingredients, has been evaluated for safety and suitability in hair dyeing applications. However, it is important to be aware of its potential side effects and other considerations to make informed decisions about its use.
Regarding individuals who are pregnant or breastfeeding, data and research on the topical usage of Hc Yellow No. 7 during pregnancy are lacking. Therefore, it is advisable for pregnant or breastfeeding women to consult a healthcare professional for further advice before using products containing this ingredient.
Side effects and adverse reactions from Hc Yellow No. 7 are generally uncommon, but they can occur. To minimize the risk of an adverse reaction, it is recommended to conduct a patch test before widespread usage.
In terms of comedogenicity, Hc Yellow No. 7 has a rating of 0, meaning it is considered non-comedogenic. This is beneficial for individuals prone to acne, blemishes, or breakouts, as it is unlikely to clog pores or exacerbate these conditions.
