The objective of this course is to impart to students the universal numbering systems of hair dyes and the chemical principles of the decoloration (hair bleaching/lightening) process on a scientific basis. It aims to enable students to analyze color pigmentation changes during the decoloration process, select the appropriate types of decolorizing cosmetics according to the structural condition of the hair, generate analytical solutions to chemical or structural problems that may be encountered during the procedure, and attain the competence to perform advanced hair bleaching and coloring applications safely and in accordance with professional standards.

This course covers the numbering systems in hair dyes and the theoretical and practical foundations of the decoloration process. Within the framework of the curriculum, color knowledge during the decoloration process, the types and chemical properties of decolorizing cosmetics, step-by-step processing procedures, technical equipment used, and contraindications (situations where the procedure should not be performed) are examined in detail. The theoretical foundation is transformed into advanced professional skill by being supported by the scientific analysis of problems that may be encountered during the procedure, solution methods, and intensive decoloration applications performed directly on hair.