This is the main factor. You need to get proof that the brand film is reliable over a long time (20 years). As the product is chemical based, the smart film is dynamic and in constant change which may be show defects over time on the Smart Glass (black spots and non-functional areas).
RAW MATERIAL QUALITY We use high class LC and PET ITO raw material. It is more expensive than others in the market but it provides the highest level of both optical and instability over time.
TECHNOLOGY There are in principle two ways to produce the Smart Film: (1) Micro Emulsion (NCAP PDLC) and (2) Phase separation. The Micro emulsion is much more complicated but provides a much better product since it keeps the spherical molecular structure. Transparency and Haze are much better than when produced in Phase separation as well as long time stability since it is water based, so it is very friendly.
Daily SHUT OFF You do not want a film that cannot work constantly. If you are required to let the film “OFF” few hours a day, it means the film is not stable.
ADDED VALUE You need to a company that will provide you with an added value based on cumulative experience. How to translate the product design for production, verify that the customer request is aligned with the product capabilities and limitations, exterior use vs. interior use, humid/wet environment etc. It is important to match the appropriate smart film and the lamination and sealing methods to the application.
EXPERIENCE You want a company that has successful track record in production and installation as the product requires a very accurate process in production as well as installation. For example, sealing with a non-qualified Silicone will damage the product.