In aerosol formulations, how are droplets propelled through a fine opening?

In aerosol formulations, droplets are propelled through a fine opening primarily by inert gas pressure. This process involves the use of a propellant, which is typically a gas that exerts pressure within the container. When the actuator is pressed, the pressure from the gas forces the liquid formulation through the small opening, creating a fine mist or spray of droplets. This mechanism is crucial for delivering the contents of the aerosol in a controlled and effective manner, allowing for uniform distribution and optimal performance of the product.

Other methods of propulsion like mechanical force, chemical interaction, or thermal energy do not efficiently provide the same level of control and consistency in the release of droplets as inert gas pressure does. Therefore, understanding the role of propellants in aerosol products is essential for effective formulation and application in various fields, including pharmaceuticals, personal care, and household products.