Final answer:
Chemical depilation uses caustic alkali preparations, such as calcium thioglycolate, to break down hair protein, allowing for temporary hair removal.
Step-by-step explanation:
The type of hair removal that uses caustic alkali preparation is commonly referred to as chemical depilation. Chemical depilatories are cosmetic preparations that often include ingredients such as calcium thioglycolate and feature a high pH maintained by calcium hydroxide or strontium hydroxide. These depilatories work by breaking down the disulfide bonds in keratin within the hair, making it weak enough to be easily wiped away after application. The typical process involves applying the depilatory cream to the desired area, waiting around 10 minutes, and then rinsing it off carefully. While these products are effective for hair removal, they do not destroy the hair follicle's dermal papilla, meaning the hair will eventually grow back.