New film selectively reflects light with any wavelength
Toray Industries Inc has released new products in its “Picasus” series of films that realize a metallic luster without using a metal.
This time, Toray said it made improvements to its polymer lamination technique and enabled to selectively reflect light with any wavelength (from visible to near-infrared light).
The Picasus is a film that realizes a metallic color by alternately stacking several hundreds or thousands of layers of different polymers and controlling the reflectance properties of light.
This time, with the improved lamination technique, Toray reduced margin of error from several tens of nanometers to several nanometers (in respect to design value). As a result, the bandwidth of wavelength in which reflectance changes was narrowed by about 90%. Being able to selectively reflect light with a certain wavelength, the company developed three new products: “near-infrared light transmitting metallic luster,” “dichroic” and “blue light cutting” films.
“With the improved nano-stacking technique, it became possible to adjust reflectance within a narrower wavelength range than before,” according to Films & Film Products Research Laboratories of Toray.
Moreover, by reducing the unevenness of lamination in the width direction of film, the variation of the entire color tone was reduced by about 50%.
The near-infrared light transmitting metallic luster film transmits only near-infrared light with a wavelength close to 950nm. When it is used for infrared sensors of TVs, faucets, etc, it makes the entire products look metallic.
The dichroic film changes its color tone in accordance with view angle. Toray expects that it will be used for preventing labels from being counterfeited, decorations, etc.
The blue light cutting film reflects only blue light, which is believed to cause eye strain. It is used to block blue light emitted from a PC display, smartphone screen, etc.
The new products are already available for sale at some places. Currently, the sales of the Picasus is several hundred millions of yen, but Toray aims to increase it by 10 times by 2020 by expanding its application.