Section 1:
Head and shoulders shampoo
Head and shoulders shampoo is for cleansing the hair and the scalp of soils and dirt. Head and shoulders shampoo are made up of many different types of ingredients, which generally include anionic surfactants, nonionic surfactants, amphoteric surfactants, glycol, polymers and water. Anionic surfactants and nonionic are served as the primary cleansing and foaming ingredients of the head and shoulders shampoo. Nonionic surfactants can both increase the viscosity of shampoo and the stability of foams. Glycol, another kind of stabilizer, not only can stabilize foams, also moisten the hair and scalp. As to the polymers, it can control the viscosity and make the hair smooth and glossy. Sometimes such as methylcellulose or hydroxyl ethyl cellulose add into the surfactant systems to increase the viscosity of shampoo as well. The last ingredient of the head and shoulders shampoo is water.
The safety ingredients must be used for manufacturing the head and shoulders shampoo because the hair-cleaning production can contact the scalp and impact the human health unconsciously. The safety ingredients mean low toxicity, low sensitization potential and low skin and eye irritation potential. However, there are several evidences that claim the head and shoulders shampoo can damage both the hair and scalp. First of all, the use of stabilizer in head and shoulders shampoo is very dangerous. For example, high temperature(over 50°c) or low temperature(under -20°c) is more likely change the stability of the shampoos (Robbins, 1994). Secondly, some manufacturers add dyestuff in the head and shoulders shampoo, many factors such as exposure to the ultraviolet radiation for a long time can cause the color instability (Robbins, 1994). Thirdly, in order to control the viscosity of shampoo, salt has been used in surfactant systems. Nevertheless, the excess of salt can decrease the viscosity.
Section 2:
Sunscreen------Coppertone Sport
Australian suffered skin cancer for a long-term time, and sunscreen is one of the most important components of protecting skin from getting sunburn and cancer. Inorganic pigments (TiO2 and ZNO) are used in most commercial sunscreens, because TIO2 and ZNO can effectively protect the skin from exposing to ultraviolet radiation for a long time. Also, organic