Mechanism 04 · Cold-air diffusion
Cold-air diffusion lets moving air carry fragrance from a scented core, with no pump, water, heat or vibrating plate. Passive designs need no power at all, and fan-assisted designs use a small, quiet fan. It is the simplest and most economical way to bring a brand's scent into a car, a bedside or a personal accessory.
How it works, where it fits and what each programme tests before making any performance statement.
How it works
Fragrance is held in a scented core, a wick or a small built-in bottle, and moving air draws the scent out as it passes. There is no visible mist. This is different from pump nebulizing, which uses an air pump to break oil into droplets: cold-air diffusion only lets the fragrance evaporate.
Where it fits
Passive designs include car vent clips, pocket-size diffusers, wearable pendants and unheated decorative stone pieces, and several of these designs are patented. Fan-assisted designs, such as bedside units, open their scent chamber only while the fan runs, so the scent is released when it is wanted. It works best in cars and close to the user, where a light, steady scent is the goal.
What to validate
Scent intensity and how long a core or refill lasts depend on the fragrance, the carrier and the airflow. They are measured for each design with the brand's own fragrance before any statement about intensity or refill life is made.
Compare the direction against the intended product context, then agree the validation plan within the ODM programme.