Dyeing
One of the defining features of construction paper is the radiance of its colors. Before the methodology behind construction paper's coloring was introduced, most paper was colored by pigments and vegetable oil, which had weaker staining capabilities, Then, synthetic dyes were developed, which provided a wider range of colors, stronger dyeing strength, and had cheap costs. However, the colors given by synthetic dyes tend to fade over short periods of time, an effect often seen in construction paper, noted by graying colors and brittleness.
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