Jojoba oil is a moisturising and emollient oil. Jojoba oil lowers the rate of transepidermal water loss without entirely blocking water vapour and gas transfer.  It improves the spreadability of cosmetic products. According to research, jojoba oil can penetrate the skin quickly through the pores and hair follicles. From there it appears to diffuse from these areas into the stratum corneum layer, where it interacts with intercellular lipids to further prevent water loss.

Jojoba oil does not induce sensitisation and primarily not a skin irritant. While it is commonly thought to be non-comedogenic, experimental tests show that it can be somewhat to moderately comedogenic depending on the potency of the oil.

See also:
Emollient
Humectants
Occlusives