Journal of Korea TAPPI ISSN:0253-3200(Print) 펄프종이기술

Color is the first visual element recognized by the human eye. It is one of the methods for distinguishing objects by the response of the eyes caused by the wavelength of light, and has properties of color, luminosity, and saturation. Over time, paper changes color due to a variety of environmental factors. In particular, colored paper is affected by the temperature, humidity, and intensity of light in the storage area, resulting in discoloration. On the other hand, materials have different degrees of discoloration depending on color. Blue with shorter wavelengths in the visible light region is more resistant than red with longer wavelengths. The experiment was conducted based on a hypothesis that yellow or red paper might absorb short-wavelength light, and would be more affected than blue paper, which absorbs long-wavelength light with lower energy. A color stability evaluation experiment was performed using commercial colored paper and dye-coated paper. Light aging experiments were conducted using a color cabinet and an accelerated weathering tester. Color differences were measured using a color difference meter. The results showed that yellow paper had the largest difference in color and was most affected by light after aging ratrer than red paper and blue paper. Additives such as glyoxal and polyaluminum chloride affect the dye color aging but show different tendencies depending on the dye’s properties.