How Window Tint Is Made

The window tint for your car, home and office is gaining popularity for more than just aesthetic reasons.  In fact, appearance has little to do with the increased use of window tinting film. Window tint is growing in popularity but it’s no longer just for looks

What drives many customers to colorize is energy savings, and ultimately cost savings.  In a world where climate change is a reality, we all want to do our part to reduce the pressure on the environment and enjoy the added benefit of reducing the pressure on our wallets. This article aims to satisfy the curiosity about “how to make window tints”. Therefore, we will take this opportunity to discuss in detail the main aspects of making window tinting films.

Reflective Window Film – How It’s Made

While there are many types of windows tinting films on the market, most, if not all, window films start with small pellets of a material called polyethylene terephthalate or PET.  This material is used for its excellent optical clarity and strength.

Phase 1 – Creating the Window Film

The pellets are first melted down into a semi-liquid state. Once in this form, the material is stretched into a polyester sheet. The process is done by pulling the material longitudinally and laterally.  Other ultraviolet (UV) blocking chemicals and materials are often added during this stretching process.

Phase 2 – Adding Metal or Dye to the Film

Next, dyes or metals are added to the polyester sheet.  Whether a dye or metal is added depends upon the intended type, quality, and function of the film.  Films that use dyes are often used on car windows because the dyes absorb a lot of heat, which allows car tints to keep the interior of the car cool in the summer.

In contrast to dyes, films using metals emit heat rather than absorb it. Metal-based films are more commonly used for flat windows and are often used for home and office tinting.

The most fascinating thing about the dyeing or metallizing process is how it is applied to mylar.  For dyeing, the dye is applied to polyester sheets and cured in an oven. The heat from the oven fuses the dye’s pigment into the polyester sheet. This fusion process ensures that the dye’s color stays in the film and doesn’t wash out. Through metallization, metals can be bonded to Mylar in three different ways.

• First, “evaporating the coating” is the process of heating the metal in the crucible to such a high temperature that the metal melts and forms a cloud of gas.  The film is then introduced into the gas cloud, and once the two cool down, the metal binds to the film.  Aluminum is typically the metal used because of its low melting point.

• Second, “electron beam coating” is the process of heating a metal by targeting a high-energy electron beam at the metal. Once heated, the coating process is the same as evaporative coating.

• Third, “sputtering” is the process of focusing a charged gas on the metal, releasing the metal molecules.  The molecules are then placed side-by-side on the film, creating a very thin and precise coating. The process is so precise that water gets trapped on the membrane during the process. The water takes several weeks to cure before it finally evaporates.

Phase 3 – Final Touches

Once the film is fused with the metal or dye, a scratch-resistant layer is applied to the side of the film that faces the interior of the home or office. This layer is designed to protect the window film from anything that might hit or scratch the window. It provides extra protection so the film can last a long time and won’t be damaged by minor scratches.

Finally, apply an industrial-strength adhesive to the window film to prolong its life and ensure it doesn’t peel or blister. Sticky adhesives are typically used for automotive window films. Clear dry adhesives using water-activated gels are commonly used for flat home or office windows.