Process Overview

Lotions, creams, and ointments are semi-solid emulsions that require precise temperature control, vacuum processing, and high shear homogenisation to achieve the desired consistency and stability. In a typical PVA Systems process plant, the oil phase (waxes, emollients, lipophilic actives) is melted in the pre-mix vessel at 65–75 °C while the aqueous phase (water, humectants, water-soluble actives) is heated separately. Both phases are then transferred under vacuum into the main mixing vessel.

Homogenisation & Cooling

The high shear homogenizer emulsifies the combined phases at rotor tip speeds of 20–25 m/s, producing a uniform emulsion with droplet sizes typically below 5 µm. Vacuum processing (−0.8 to −0.9 bar) eliminates entrapped air, preventing micro-bubbles that cause instability and oxidation. The batch is then cooled under slow agitation to the filling temperature (25–35 °C), during which the product develops its final viscosity and texture. The entire cycle — heating, emulsification, and cooling — is completed in 60–90 minutes, compared to 3–4 hours with conventional open-vessel methods.