Influence of different cosmetic vehicles in mechanical and physical properties of hair treated with oxidative hair dyes

ABSTRACT Hair care products play a significant role in the cosmetic market and aim at improving hair brightness, breakage resistance, and color change. In this study, we analyzed the possibility of the formulation of oxidative dyes in different vehicles impacting the hair’s both mechanical and physical properties. Light brown and light blond dyes were prepared using eight different vehicles. Among these, four vehicles were emulsifying agents and four gelling agents. Each formulation was applied to two types of virgin Caucasian hair (light blond and dark brown). Physical, chemical, and organoleptic properties of each formulation were assessed, as well as changes in hair parameters after oxidative dyeing, such as staining intensity, brightness, and breaking strength. The parameters of color and brightness differed in some formulations, but the hair type also responded differently. Brightness parameter was increased in dark brown hair colored with both dyes, whereas light blond hair showed the opposite result. Regarding the breaking strength, there were no significant differences between the two kinds of tresses. Cosmetic formulations should adjust the consumer desired effects (e.g. color change) in order to present minimal drawbacks (e.g. decrease of hair brightness and strength). Thus, the study of different vehicles is important when establishing the best oxidative dye formulation.

摘要：护发产品在化妆品市场中占据举足轻重的地位，其核心目标为提升发丝光泽度、增强抗断裂性能并实现色彩调整。本研究针对不同赋形剂（vehicles）中氧化染料（oxidative dyes）的配方可行性展开分析，探究其对发丝机械与物理性能的影响。本研究采用8种不同赋形剂制备了浅棕与浅金棕两种染发剂，其中4种为乳化剂，剩余4种为胶凝剂。将各配方分别施用于两种未染过的原生高加索人发丝：浅金发丝与深棕发丝。研究对每种配方的物理、化学及感官性能进行了评估，同时检测了氧化染发后发丝的各项参数变化，包括染色强度、光泽度与断裂强度。部分配方的色彩与光泽度参数存在差异，且不同发质的响应表现也各不相同。使用两种染料染色后的深棕发丝，其光泽度参数均有所提升，而浅金发丝则呈现出相反的变化趋势。就断裂强度而言，两种发丝样本之间未出现显著差异。化妆品配方应兼顾消费者的预期功效（如色彩变化），以尽可能减少负面影响（如发丝光泽度与强度的下降）。因此，在优化氧化染料配方时，针对不同赋形剂的研究具有重要意义。