Many people have a similar feeling after washing their hair or using conditioner: their hair is smooth and smooth, because the mainstream shampoo products on the market contain polydimethylsiloxane, commonly known as silicone oil. Silicone oil is the common name of polydimethylsiloxane which is liquid at room temperature. It is a kind of mineral oil. It has viscosity and ductility, and can moisturize and soften hair. Hair is from the hair follicles in the scalp, the main component is keratin. There are many uneven scales on each hair. When the hair scale is damaged, it will curl up, which will increase the friction between the hair and cause the hair to tangle together. More friction will aggravate the damage of the hair scale. When shampooing, the silicone oil in the shampoo will adhere to the gap between the hair scales, fill the hair surface, bring the hair quality "repair" effect, and the hair will feel very soft.

Ancient women used osmanthus oil to comb their hair, but now people use silicone oil products to wash and protect their hair. Since the 1950s, silicone oil was initially used in personal care products. Since the 1970s, silicone oil has been widely used in shampoo and hair care products. However, the ingredients of vegetable oil, cetyl alcohol and other ingredients have been used for thousands of years.

It is understood that before the 1990s, China's domestic daily chemical products almost did not use silicone oil as a raw material. Around 2000, silicone oil began to be brought into the Chinese market by international daily chemical brand products. At first, its price was high. Then, with the decline of silicone oil raw material price, it gradually became one of the widely used raw materials for washing and protecting products. According to Dr. Yang Jianzhong, an expert in hair washing and hair care, the proportion of hair care products containing silicone oil has reached more than 90% in the Chinese market.