Regarding optically variable pigments, we often come across them in our daily lives. Optically variable pigments are widely used in packaging of various products, decoration of items, and color matching in the cosmetics industry. Different types of optically variable pigments are used in different applications. Here, we introduce a new type of advanced optically variable pigment - the optical interference color-shifting pigment.

What distinguishes this pigment from ordinary pearl pigments is that its composition does not include a substrate, but is composed of multiple layers of nano-scale thin films. The colorful effect is achieved by the interference changes between the layers of thin films. Additionally, as multiple layers of thin films are stacked, a three-dimensional color change effect and a shiny metallic luster effect can be presented.

The technical principle of this new type of optically variable pigment is similar to that of other optically variable products, both based on the principle of optical interference and presenting different colors depending on the angle of the incident light. However, it uses materials composed of multiple refractive indices. In order to achieve optical color-shifting, the principles of physical meteorology sedimentation need to be referred to accurately control the size and sequence of each layer of thin films, allowing them to settle regularly on the same carrier. When the incident angle of light is different, the equivalent optical path length through the layers of the optically variable pigment will be different, resulting in spectral shifts and reflecting or refracting different colors.