Myristyl myristate is the ester of the fatty alcohol myristyl alcohol and the fatty acid myristic acid. The result is a highly versatile cosmetic ingredient that works to improve texture, enhance spreadability, add opacity to creams, serums and lotions, offer emollient skin care properties and offer a non-greasy occlusive finish that helps prevent dehydration.
Usage levels in cosmetics range from 1-10% depending on formulation needs such as desired aesthetics. It is considered safe as used in cosmetics. https://www.paulaschoice.com/ingredient-dictionary/ingredient-myristyl-myristate.html?q=Myristyl%20Myristate&fdid=ingredients