Non-color application of packaging design

Color is divided into two categories: achromatic and color. Achromatic is black, white and various grays from dark to brightest. They can be arranged into a series, called black and white series. The change from black to white in this series can be represented by a gray band, one end is pure Black, the other end is pure white. The substance reflects all visible light, and the reflectivity equals 100% is pure white; the substance absorbs all visible light, and the reflectivity equals 0%, pure black. In actual life, there are no pure white and pure black substances. Magnesium oxide can only approximate pure white, and black velvet is close to pure black.

The achromatic color of the black and white series can only reflect the change of the light reflectance of the substance, and the visual perception is a bright change.

When the reflectivity of the surface of the printed matter to the radiation of all wavelengths of the visible spectrum is above 80% to 90%, the visual perception is white. If the reflectance is below 4%, it is black. White, black, and gray objects are not selective for the reflection of each wavelength of the spectrum, and they are called neutral features.