Hair is an important part of a person's image, so it's essential to use the right products for hair care. The most important hair care products are shampoos, which gently cleanse and nourish the hair and scalp. There are several types of shampoos, each aimed at caring for a different hair type, which requires different ingredients. The most important substances for hair cleansing are surfactants. Other important ingredients in shampoos are. Thickeners, emollients, humectants, preservatives, pH adjusters, perfumes, coloring agents, and cosmetically active ingredients.
In this diploma thesis, we reviewed 60 shampoos found in drugstores and websites. We divided them into 5 groups, according to the hair type they were intended for. We focused on the 4 basic groups of surfactants and their frequency of occurrence in shampoos for different hair types. In shampoos for dry or damaged hair and colored hair that need more intensive care, we also looked at emollients and humectants.
Non-ionic surfactants are the most diverse, with 24 different types. While anionic surfactants, especially sodium laureth sulfate, are the most common. This surfactant is present in 49 shampoos, 48 of them in the 2nd position on the INCI list, which identifies it as a primary surfactant. Primary surfactants have the highest cleaning power but can be irritating to the skin, so non-ionic or amphoteric surfactants are added to them to mitigate the effect. Cocamidopropyl betaine was observed in 49 shampoos, in 42 together with sodium laureth sulfate.
In most shampoos, the PAS appears in the 2nd position of the INCI list and is usually an anionic surfactant. However, all shampoo types contain on average the same number of surfactants in their composition.
We also looked at thickeners in shampoos, the most commonly used thickener being sodium chloride, which is present in 58 shampoos. We focused in more detail on shampoos for the care of dry or damaged hair and colored hair. We looked at the most commonly used emollients and humectants. In a review of 24 shampoos, glycerol was the most frequent humectant and castor oil was the most frequent emollient. Compared to the other shampoo types, these two contained on average more emollients but fewer humectants.
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