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.
Propylene Glycol is a useful componet with many positive effects. It’s a very good moisturizer. It helps to deliver ingredients into deeper layers of the skin. It creates a protective layer on the skin preventing water loss. The component is researched very well and doesn’t have notable side effects. It’s used even for making food.
Sodium Lactate is very effective for recovering the natural lipid layer of the skin. It’s safe and doesn’t provoke negative reactions. It provides a strong moisturizing effect. It’s a nice soothing ingredient.
Sodium PCA is a nice moisturizer and skin softener. It contains amino acids and Sodium Hyaluronate. It’s part of the Natural Moisturizing Factor (NMF) that is responsible for keeping the outer layer of the skin hydrated. If you don’t have enough NMF you can face dryness even if you don’t have other skin problems.