Why are there glass balls in spray can?

In our daily life, we commonly see aerosol products, such as spray paint and snow spray, which seem to be simple, but actually contain a lot of design ingenuity, in which the existence of marbles has a unique meaning.

Aerosols such as spray paints and snow sprays are filled with a liquid with a specific functional ingredient, which is sprayed out as a mist under pressure when in use. The marble is the key component that ensures that they work stably and efficiently.

In terms of marble size, most common marbles have a diameter of between 6 to 20 mm. For paint spraying, the diameter (e.g. 16-20 mm) of the marbles is more appropriate. When the marbles roll inside the aerosol can, they can stir the paint more frequently and meticulously, so that the pigment particles are uniformly dispersed in the solvent, ensuring that the sprayed paint mist is fine and even, thus forming a smooth and even film on the surface of the object to be sprayed, and improving the quality of spraying. For example, in automotive painting, a fine mist of paint gives a natural colour transition and a high-quality appearance to the bodywork.

Snow spray generally uses marbles with a diameter of 6-10 mm. The principle of snow spray is to simulate the effect of falling snowflakes by spraying white foam. This size of marbles can stir the foaming agent and other ingredients inside more powerfully, so that the sprayed foam is more fluffy and even, creating a more realistic snowfall effect, which can bring better visual experience to people in festivals, stage performances and other scenes.

The number of marbles is usually between 1-3pcs. A single marble is suitable for small aerosol cans or products with relatively low mixing and blending requirements. When the space inside the can is limited, a single marble can move sufficiently in the limited space to provide basic mixing. For larger aerosol cans, or for paints and flying snow sprays where mixing of the internal components is more difficult, 2-3 marbles working at the same time will be more effective. Multiple marbles rolling and colliding in different positions inside the can will agitate the liquid in all directions and more efficiently, ensuring an even distribution of ingredients.

The benefits of marbles in aerosols are manifold. From the agitation and mixing point of view, it prevents the ingredients within the aerosol from settling and layering. The pigments and solvents in the spray paint are easy to separate after a long period of standing, with the marbles continuously stirring, each time the nozzle is pressed, the sprayed paint is of the same composition, uniform and stable colour and texture; Snow Spray's blowing agent and other additives can also be fully mixed under the action of the marbles to spray a stable foam. In terms of spraying performance, the marbles help to maintain stable pressure in the tank. During the spraying process, the rolling of the marbles can make the liquid flow more smoothly, avoiding local blockage or uneven pressure leading to poor spraying, ensuring that each spray can be stable and continuous, making it more convenient for the user to operate and enhancing the product experience.