Different Types of Window Film For Automobiles

Many window film options are available to fit cars and trucks, with various appearances, properties and costs to suit all applications and tastes.

Polyester film is the common factor in all the types of window film. This may be a single or multiple layers of varying depths, typically between 2 and 7 mm. There will be an inner surface with a pressure sensitive or water activated coating, and a hard, protective outer surface to make the film scratch-resistant. These basic properties provide some shatter resistance. Specific levels of ultraviolet protection can be achieved by adding chemical UV blockers - cyclic imino esters - to reflect various proportions of UV radiation.

Three production technologies and combinations of them are used to give the finished window film product particular features and characteristics: dyed film and two different metallizing processes that create deposited film and sputtered film.

1. Dyed Film

Applying dye to the film has obvious benefits for darkening, tinting, and privacy; however, its main purpose is to absorb heat. This protects the interior of the vehicle from heating up excessively, as the heat absorbed by the film transfers to the glass, and is then dissipated by airflow outside.

This does require some air movement around the surface of the glass, so a stationary car on a hot, still day is going to allow a small amount of heat through the film, and the inside of the car will slowly heat up. However, average natural air movement of 15mph means there is nearly always enough breeze to keep the vehicle cool.

An example of dyed film

Disadvantages of dyed window films include limitations to its appearance: there is always a certain amount of reflectivity to dyed films. Also, they are not suitable for double-glazed windows. Thermal glass windows restrict air movement between the panes of glass, which prevents the inner pane from dissipating heat. If you require a film suitable for these types of window, one of the other coating technologies should be considered.

2. Deposited Film

This type of film introduces a metallized protective layer to protect the reflective coating, and reflect heat away before it can reach the glass. A further film layer protects the metallic coating, which is applied by passing the film through a pressurized vacuum tank, where particles of nickel-chrome, aluminum or copper cover the surface of the film. The concentration of the metal coating depends on how quickly the film is passed through the vacuum chamber.

Deposition is a relatively low-cost process, although the range of metals available is limited, and the tints are darker and more reflective than other processes because the coating needs to be relatively thick. The weight of the metal coating also means the film naturally attracts a certain
amount of heat.

3. Sputtered Film

Sputtering is a more advanced form of metallizing, offering more than 25 distinct metal coatings and a much lighter end product than deposited film. The blend of metal coating can be highly specific for blocking certain bands of radiation from sunlight and may be as fine as a hundredth of a human hair's width.

Sputtering is a highly complex atomic process that takes place inside a vacuum chamber filled with inert argon gas. Electromagnetic fields blast the metal with ions, which dislodge short bursts of atoms, evenly coating the surface of the film with a fine layer of metal.

Sputtered films are more expensive than those produced by the other processes. But they offer more effective performance and many more options for custom properties, with high radiation reflectivity and minimal levels of color shift, mirror effect and heat absorption. Polyester layers with adhesive and scratch resistant coatings are a feature of sputtered window films.

4. Hybrid Films

A blend of dyes and metals can combine the best qualities of both types and minimize the drawbacks. Companies, such as, hire us to do window tinting - http://www.windowtintinglasvegasnevada.com, reccomend this for its many benefits. For example, a hybrid film with gray dye and titanium coating is brighter than a darkened, gray dyed film, and has much less of a mirrored appearance than a titanium coated film.

With the choice of coatings and colors available, customers can choose a darker window film for privacy without the need for a high resistance. With hybrid films, there is no longer a connection between the darkness of the window film and its heat resistance.