Antiperspirants are a personal care product used to keep you dry, and are typically applied to parts of the body that tend to sweat, such as the underarms. Antiperspirants have two functions: they reduce the amount of sweat that reaches the surface of the skin and they inhibit the growth of bacteria that cause body odor. The aluminum salt commonly used in antiperspirants is aluminum hydroxychloride. It effectively inhibits sweating and sweat odor. It reduces sweating by forming small crystals at the mouths of the channels through which sweat flows. Insoluble aluminum is also used as a coloring pigment in lipsticks, and in toothpastes where it is used to eliminate staining of teeth caused by tea or coffee.
Hydroxyaluminum chloride is the main active ingredient in spray antiperspirants. In addition to the active ingredient, the compressed gas is the carrier medium and the aluminum salt component is suspended in powder form. Due to the principle of constant thermal expansion, the compressed gas will cool the spray to a certain extent, giving a cooling sensation to the sprayed antiperspirant, but it should be noted that it should not be sprayed for a long time. Follow the product instructions when storing or using the spray.
Walk-on antiperspirants are clear or emulsified, and their carrier media is a liquid such as water or alcohol, with the active ingredient hydroxyaluminum chloride present in either solution or suspension.
Upon contact with the skin surface, the aluminum salt component dissolves in the sweat or moisture on the skin surface, thus becoming gel-like. This process greatly reduces the flow of sweat secreted to the skin surface, in the form of water. As a result of daily actions such as bathing, the aluminum salt component that absorbs sweat separates from the skin surface, so the amount of sweating returns to normal.