Minnesota Cosmetology State Practice Exam 2025 - Free Cosmetology Practice Questions and Study Guide

In the context of hair color formulations, ammonia serves a crucial role as a key ingredient. Its primary function is to open the hair cuticle, which allows for better penetration of color molecules into the hair shaft. This is essential because hair color needs to effectively reach the inner layers of the hair to provide long-lasting results.

While hydrogen peroxide is also a significant ingredient as it acts as an oxidizing agent, working in conjunction with ammonia to develop the color, it is ammonia that is most commonly recognized as a fundamental component in the majority of traditional hair coloring products.

Alcohol and pectins do not serve the primary purpose of altering hair color. Alcohol can be present in some formulations primarily as a solvent or to help with consistency but is not used for the color process itself. Pectins, on the other hand, are typically found in food products or used as thickening agents and are not relevant to hair coloring formulations. Thus, ammonia remains the most prevalent ingredient in the formulation of hair color products due to its vital role in color development and penetration.