Water is a great solvent. It’s neutral and doesn’t provide any strong positive or negative effects. It just helps components to mix better and to transport active components.
Dimethicone is the most popular silicone. It makes the skin softer and forms a film adding smooth and silky feeling. This film not only improves how the skin feels but also works as a protective barrier. It also improves the visual appearance of your skin by filling small wrinkles. What you should really know is that this component is difficult to wash off! So make sure you did proper cleansing after using it.
C12-15 Alkyl Benzoate is mostly used as formulation component. It gives the product a soft and silky but non-greasy feeling. As for the skin benefits, it's an emollient – it makes the skin softer and more hydrated. It also helps to kill bacteria and increase the product’s shelf life.
Isododecane is an emollient and a good base for colorants. Very often used in powders and shades because it spreads on the skin nicely. It also helps to soften the skin and helps to lower water loss making all the moisturizing components work better.