Here are all your questions about the newest thing in window film, answered.
Photochromic window films are the next generation of retro-fit window film technology. Designed to adapt to your environment, photochromic window films share all the same benefits of conventional window films but have a special adaptive feature craved by homeowners and building design professionals – the ability to darken when exposed to sunlight, further reducing heat and sun glare streaming through glass when needed most.
What does photochromic mean?
Literally speaking, photochromic is the combination of two words: “photo” meaning ‘light’ and “chromic” meaning “colour”.
What is photochromic?
Photochromic is a characteristic of special molecular compounds. These ‘smart’ nanomaterials experience a reversible change of structure when exposed to UV radiation. This change of molecular structure manifests itself as an adaption of color. Technically speaking, this is a reversible photochemical reaction where an “absorption band” in the visible part of the electromagnetic spectrum changes dramatically in strength or wavelength.
How About a Non-Technical Answer?
Sure. The UV radiation from the sun triggers a change to the structure of a photochromic compound. This change in structure is invisible to the naked eye yet creates the condition where a portion of the visible light spectrum – the light we see – is blocked by the activated molecule. When additional portions of the light spectrum is blocked, we experience a colour change to a darker, more tinted state. When the radiation is removed, like at nighttime, the structure recomposes and the colour change reverses.
What is the difference between thermochromic, electrochromic and photochromic?
All three of these terms define characteristics of smart materials that undergo a structural change as a result of external stimuli like stress, radiation or electricity. Thermochromic material is activated by heat energy. Electrochromic material is activated by electrical current. Photochromic materials are activated by UVA radiation. All of these actions are reversible once the external stimuli are removed.
How do photochromic materials and window films work together?
Window films are constructed with many layers of materials laminated together to function a certain way. Solar window films are typically layers of adhesives and polyester (PET) treated a variety of ways depending on the intent of the window film. The patented thermal functional layers within CoolVu are micro-thin coatings of special photochromic carbon based molecules. These interlayers provide for the climate responsive nature of the CoolVu transitional window film product.
How is CoolVu Transitional Window Film manufactured?
CoolVu is similar to most of today’s higher-end window film products that are ‘sputtered’ and coated with special ceramic heat blocking nanoparticles. Sputter deposition is a physical vapour deposition (PVD) method of thin film deposition by sputtering. This involves ejecting material from a “target” that is a source onto a “substrate” – in this case, the PET. Different sputtered materials (mostly metals) will yield specific results and aesthetics once deposited onto PET. Utilizing German made sputtering technology, Japanese coating machines and utilizing American made PET and adhesives, CoolVu is a patented process that has resulted in the world’s first stable photochromic retro-fit window film product.