Косметические ингредиенты

The minimum composition of a stable O/W emulsion: emulsifier (Olivem 1000 or Polawax, 4–8%), oil phase (jojoba, 5–15%), glycerine (3–5%), water (up to 100%), preservative (phenoxyethanol, 0.5–1%). Active ingredients are added after the base formulation has been stabilised.

Determine the type of emulsion: O/W (light cream, lotion) – HLB 8–16; W/O (thick protective cream) – HLB 3–6. Calculate the weight-averaged HLB of the oil phase and select an emulsifier with a matching value. HLB data for oils can be found in the technical specifications for each product

Amphoteric and non-ionic surfactants instead of anionic ones, bisabolol, allantoin, panthenol, and mild preservatives without formaldehyde donors. In barrier formulas: ceramides and phytosphingosine at a pH of 4.5–5.5.

 L-ascorbic acid is active at a pH of 2.5–3.5. Peptides are deactivated at a pH below 4.5 due to the hydrolysis of their bonds. It is not possible to combine them in a single formulation. Solution: stable derivatives of vitamin C (ascorbyl glucoside, MAP, SAP) with a working pH of 5.0–7.0 are compatible with peptides.

The base should be an anionic surfactant (SLES or cocosulphate), with a co-surfactant being amphoteric (cocobetaine, CAPB). Cationic conditioning agents are added via an amphoteric buffer — not directly with the anionic surfactants: otherwise, an insoluble precipitate will form.

HLB (Hydrophilic-Lipophilic Balance) is a numerical indicator of the balance between the hydrophilic and lipophilic parts of an emulsifier molecule. It determines the type of emulsion being stabilised: O/W (HLB 8–16) or W/O (HLB 3–6). A mismatch in the HLB values of the oil phase and the emulsifier is the main cause of phase separation in the finished product.