Strictly speaking, the colorful board is not a single material of acrylic sheet, the colorful board is made of acrylic sheet as the main substrate, in the back of the acrylic hot-pressing a layer of PET material made of colorful film. Dazzle board colorful, mainly from its back of the rainbow film, then what is the rainbow film? Rainbow film is a variety of different refractive index of PET plastic melt extrusion, and a spaced stack of more than 100 layers, the thickness of each layer is only a few hundred nanometers of the multilayer composite film, the overall thickness of the film between 16μ-36μ. It is mainly divided into three series: green light on red background, gold light on blue background and purple light on blue background. At different distances and angles, the light effect of the rainbow film itself will show completely different luster effects.