In cosmetics and personal care products, Triethanolamine may be used in some makeup products such as eyeliner, mascara, eye shadow, blush, make-up bases and foundations, as well as in fragrances, hair care products, hair dyes, wave sets, shaving products, sunscreens, and skin care and skin cleansing products. Ethanolamine may be used in some permanent waves and hair dyes and colors. Diethanolamine itself is rarely used in cosmetics, but derivatives of DEA may be used in shampoos and cleansing products. TEA, DEA and Ethanolamine help to form emulsions by reducing the surface tension of the substances to be emulsified so that water-soluble and oil-soluble ingredients can be blended together. They are also used to control the pH of cosmetics and personal care products. Recommended use for Making Cosmetic & Making Soap.