Fake snow is a blanket term for materials used to simulate a winter environment for decorative, theatrical, or novelty purposes. The specific composition depends entirely on the intended application, whether for a small novelty item or a massive film set. These materials are engineered to mimic aspects of real snow, such as its fluffy texture, white appearance, or the way it settles and falls.
The Expanding Polymer
The most common novelty version of fake snow, often sold in small kits, relies on a substance called sodium polyacrylate. This white powder is a superabsorbent polymer, meaning its chemical structure allows it to take in huge amounts of liquid relative to its own mass. The polymer consists of long, coiled molecules that are cross-linked into a network.
When water is added to the powder, the polymer instantly begins to swell as the water molecules move into the spaces within the network. The sodium polyacrylate molecules dissociate into negatively charged ions, which repel each other. This repulsion causes the polymer chains to unravel and expand significantly. This rapid expansion traps the water, forming a fluffy, snow-like gel that can absorb hundreds of times its weight in water.
Dry Flakes and Aerosol Sprays
For static, non-expanding indoor decorations, such as dressing Christmas trees or window displays, the composition changes entirely to dry flakes and aerosol applications. Dry flake snow is typically made from fine, lightweight materials such as polyethylene plastic flakes, finely ground mica, or cellulose pulp. These materials are scattered onto surfaces where they adhere due to static electricity or are applied with a mild adhesive.
Aerosol, or flocking, sprays deliver a snow-like residue from a pressurized can, designed to stick to surfaces permanently or semi-permanently. The residue is often a mix of lightweight white particles, such as calcium carbonate, finely ground wood pulp, or a saturated fatty acid like palmitic or stearic acid. These solids are mixed with a binder, such as polyvinyl acetate or an acrylate resin, which acts as a glue. A solvent and a propellant are also included to allow the mixture to be sprayed evenly, with the solvent evaporating quickly to leave behind the sticky coating.
Large-Scale and Prop Materials
When simulating deep snow or a blizzard on a movie set or for a large commercial display, specialized materials are chosen based on scale, safety, and environmental impact. For wide-area ground cover, a large volume of non-adhesive, cellulose-based snow is often used.
This paper-based snow, known by trade names like SnowCel, is essentially shredded paper or wood pulp fibers, which are sometimes treated to be flame-retardant for indoor use. It can be blown through specialized machines to create the effect of falling snow or layered to form drifts.
Another option for close-up shots or environmentally sensitive areas involves biodegradable starch-based materials, often derived from corn or potato starch, which are completely non-toxic. Older methods for creating falling snow involved machines that release specialized foam liquids or soap flakes, which dissolve after a short time, offering a realistic snowfall effect without extensive cleanup.