Solar Control Window Film: Improves Indoor and Outdoor Thermal Environments/Shatterproof for Disasters
Dexerials Corporation
| Publication date | December 02, 2016 (Posted on September 9, 2022) |
|---|---|
| Sector | Life of Citizenry and Urban Life |
Company Overview
Dexerials Corporation has been manufacturing and selling Albeedo, a solar control window film, since 2012. Albeedo is a new type of transparent retro-reflective window film that reflects only near-infrared rays back towards the sky. Our original spectrally-selective reflective film that we developed allows most of the visible light in solar radiation to pass through as it is, but selectively reflects near infrared rays back towards the sky to reduce the amount reflected to the ground. By applying this retro-reflective film onto the interior of the window glass of a building, near infrared rays will be blocked from passing through, controlling the rise of indoor temperature, while improving the thermal environment around the building at the same time. This will contribute to the thermal adaptation of the walking areas and mitigation of the urban heat island effect.
Adaptation Initiatives
- Our focus: Conventional energy-saving methods for windows (high reflective technology such as Low-E glasses) can save the indoor energy, but they become one of the causes of the urban heat island effect since near-infrared rays reflected toward the ground can be absorbed and accumulated in the streets.
- Approaches: We have been working on a film for LCDs that controls the direction of the image light and have utilized this technology to architectural applications to complete a window film as a measure to mitigate and adapt to the urban heat island effect and global warming that become increasingly serious. We have been expanding the proposal of this product not only in Japan but also overseas. The film also has shatterproof performance, making it possible to prevent glass from shattering in the event of window breakage due to a disaster.
- Adaptation: As can be seen from the data provided by the Ministry of the Environment, the source of heat in the summer is not limited to direct solar radiation, but also the accumulated radiant heat from the walls and ground (figure below)
Source
- Ministry of the Environment, Heat illness prevention website
However, Albeedo can improve the solar reflectivity of the local covered surfaces by retro-reflection. It has an adaptive effect by reflecting most of the solar heat that incident on the local surfaces back to the sky, which controls the heat from the solar radiation in the walking area. This also contributes to mitigation of the urban heat island effect by reducing the heat absorbed and accumulated within the building frame and the ground.
The performance has been verified by demonstration experiments.
Using a special device that blocks direct solar radiation and only measures the effect of reflection from the window, the comparison showed, at the floor temperature in exterior near the window glass (when in black), “Albeedo” applied glass indicated approximately 8°C lower than the Low-E glass.
