Propylene glycol (1,2-propanediol)' means a dihydric alcohol which, due to its chemical and physical properties, is widely used in pharmaceuticals, cosmetics and technology both as a monosubstance and as a component of an ester, 'caprylates' means salt/esters of caprylic acid (n-octanoic acid), 'caprate' means salt/esters of capric acid (decanoic acid).
Propylene glycol dicaprylate is used in cosmetic formulations. The substance acts as emollient (makes the skin smooth and supple).