| abstract |
A transparent substrate and a low-radiation coating formed on one surface of the transparent substrate are included, and the low-radiation coating includes a first dielectric layer, a second dielectric layer, and a third dielectric layer sequentially laminated from the transparent substrate. The first including a body layer, a first low radiation protective layer, a low radiation layer, a second low radiation protective layer, a fourth dielectric layer, a fifth dielectric layer and a sixth dielectric layer. The refractive index of the dielectric layer and the refractive index of the third dielectric layer are lower than the refractive index of the second dielectric layer, respectively, and the refractive index of the fourth dielectric layer and the sixth dielectric Provided are functional building materials for window doors in which the refractive index of the body layer is lower than the refractive index of the fifth dielectric layer, respectively. |