abstract |
Provided is a thermal barrier film having, dispersed in a resin matrix, high-refractive-index particles having a D-line refractive index of 2.5 or more and 3.2 or less. The high-refractive-index particles have an average particle size of 2.0 μm or more and 5.0 μm or less. Provided are a thermal barrier film that reduces a temperature rise due to sunlight by virtue of having a high reflectance even as a thin film, has high film thickness accuracy, and has high abrasion resistance, a thermal barrier paint for forming such thermal barrier film, and an optical instrument including such thermal barrier film. |