Newsprint has low basis weight, low whiteness and good bulk, with the progress of production technology, newsprint is gradually used for color printing; coated paper is coated on the surface of base paper, which has high smoothness, high whiteness and high gloss, the printing color is bright, the layers are clear, and it is often used for the printing of fine products; the coated white board is a coating on the surface of the white board, which has good smoothness, good gloss and high stiffness, and is often used for product packaging. There are differences in physical properties such as smoothness, gloss, ink absorption, whiteness, and bulk of these three papers.
After experimental tests, newsprint has the best bulk, the lowest whiteness, the highest PPS roughness, the worst gloss, and the lowest opacity; the art paper has the highest tightness, the highest whiteness, the lowest PPS roughness, the best gloss, and the opacity. High; Coated white paperboard has better bulk, high whiteness, low PPS roughness and better gloss. The pulp for newsprint production is mechanical pulp, which retains the lignin as much as possible during the production process, with low whiteness and good bulk, but the newsprint has low basis weight and low opacity compared to coated paper. Coated paper and white board are coated with paint on the surface of the base paper, and the pigment in the coating fills the uneven depressions on the paper surface. After calendering and finishing, the pigment particles are arranged in a directional arrangement, which reduces the roughness of the coated paper and white board PPS and increases the smoothness. Since the gloss mainly depends on the smoothness of the paper surface, the gloss of the paper (board) is in the opposite order of the roughness of the PPS, that is, coated paper > white cardboard > newsprint.
The printing gloss is affected by the smoothness of the paper surface and the ink absorption performance. The paper coating can significantly improve the printing gloss of the paper. The surface of the newsprint is rough and has good ink absorption. The printing gloss is only 17.6%, and the surface smoothness of the coated art paper is high. , The ink absorption is moderate, the printing gloss is 86.6%, and the printing gloss of the coated white board is 82.4%.
Papers with moderate ink absorption, and higher gloss, produce the most saturated colors. A matte paper that is 100% absorbent will print very poor colors. The paper surface efficiency of coated paper is the highest, followed by coated white board, and the paper surface efficiency of newsprint is the lowest. Appropriately reducing the ink absorption of newsprint and reducing the PPS roughness of newsprint will help to improve its paper efficiency.
Post time: Aug-29-2022