Defining The Types of Window Film

The term window film, although seemingly new, actually dates back to the early 1960s. While window film has many uses today, then, it was designed to control the climate within buildings due to sunlight. Early films reflected the sun back away from the window or the interior of a building while allowing those inside to still see out. The film was transparent. As this concept grew, the demand for colored films also began to grow. These colorized films soon became integrated into a buildings architectural design. Colorization of film included colors such as bronze, gray, gold and amber.

Then came the energy crisis in the 1970s. With this, more people became interested in the possibilities of window film and the saving of energy. This was followed by the study of window film and its efficiency. Early window film was made of polyester, which was 2 to 7 milliliters thick. Several thick layers of this film were often bonded together. One side was coated with a pressure-sensitive or water-activated adhesive. The exposed surface was in turn treated with a hard, scratch-resistant coating. Chemical UV blockers called cyclic imino esters, were imbedded in the film. The film’s sole purpose was to provide only UV protection and to shatter resistance to glass.

The problem with the early film was that it tended to absorb and reradiate long wave infrared heat rather than act as a transparent medium. But this all changed as demand continued to grow for something more efficient. Today, window films are highly technological so that they can meet a number of requirements.

So what types of film is on the market today? According to Popular Mechanics, the most common four include:

1. DYED FILM - This film is single-ply and dyed with a standard scratch resistant coating. While this sounds simple, three separate technologies are applied to achieve different performance characteristics for this film. The heat rejected by the film is stored largely in the glass and is drawn away by external air movement. The other two processes, called deposition technology (vacuum coating/metallizing) and sputtering technology (advanced metallizing), deposit a layer of metallic particles on the film, giving it a reflective coating. In each case, a second layer of film protects the coating. Metallized films reject heat by reflecting it before it can be transferred through the glass.

2. DEPOSITED FILM - The technology of this film has to do with the deposits put into it. For this film to be effective, the metallized coating must be fairly thick, as the particles are comparatively large. This film produces a darker, more highly mirrored surface.

3. SPUTTERED FILM - This film is a two-ply metallized window film with metallized and UV treated film layers. The practical benefits of sputtering are that 25 to 30 different metals can be used and the metallized coating is much lighter. Different metals are chosen to subtract specific bands of radiation from the solar spectrum. The result is a highly reflective layer with very little mirror effect, heat absorption or color shift. Because sputtering is more expensive, these films occupy the high end of the price range. Metallic films control radiation through reflectivity. Simplified film consists of polyester layers, metallic coating, adhesive and scratch-resistant coatings.

4. HYBRID FILM - This film is made by combining dyes and metals. An example would be a combination of gray dye and titanium coating - paired, these two result in a film that is bright and no reflective.

Window film has come a long way as newer technology is always replacing older. Each change typically brings with it a more efficient and cost saving product.

John O'Brien, Vice President of InVision Window Tinting, is a knowledgeable and leading provider of San Antonio window tinting. He is known as one of the best residential and commercial window tinting San Antonio providers. For more information, please visit http://www.invisiontint.com.