HARDBOARD HAVING HIGH LIGHT-SHIELDING PROPERTIES

摘要

PROBLEM TO BE SOLVED: To provide a hardboard that has high shielding action from the light with wavelength from 250 nm-850 nm, causes no migration of the coloring dyes or pigments to the content in the package and is suitable for the purpose of food packaging. SOLUTION: This hardboard comprises at least the outer layer, the intermediate layer and the back layer where the intermediate layer includes chemical fibers that are colored by kneading inorganic pigments therein. The amount of the colored chemical fibers is 12-60 g/m2 in the intermediate layer and the proportion of the inorganic pigment kneaded is 1-50 wt.% in the chemical fibers.