How do people put colour into cellophane?

Color is added to cellophane during the manufacturing process through the incorporation of dyes or pigments into the cellulose material before it is extruded. These colorants can be either water-soluble or solvent-based, depending on the desired properties of the final product. Additionally, some manufacturers may apply color coatings to the surface of the cellophane after it has been produced. This allows for a wide range of colors and finishes, enhancing the aesthetic appeal of the material.