Effect of Pulp on the Strength of Coloring Paper Used for the Production of Fruit Bags

Abstract

In the present study, we explored an eco-friendly method for improving the strength of base paper for fruit bags. We determined the fibers characteristics of hardwood bleached kraft pulp (HwBKP), recycled liquid crystal display glass interleaf (LCD), and old newsprint (ONP), which are raw materials used to produce coloring paper. Using various types and mixing ratios of pulp, we produced coloring paper handsheets and determined their strengths. The HwBKP had the highest initial freeness, and as the freeness decreased, the strength of the handsheet increased. The ONP had the lowest initial freeness and paper strength owing to a high recycling rate. The LCD interleaf comprised softwood fibers and was stronger than a handsheet with a Canadian Standard Freeness (CSF) value of 450 mL made from HwBKP. However, when the freeness of HwBKP was 350 mL CSF, the handsheet strength decreased as the mixing ratio of LCD interleaf increased. Therefore, we concluded that it was necessary to decrease the freeness of HwBKP or increase the mixing ratio of LCD interleaf while maintaining the freeness of HwBKP at 400-450 mL CSF to enhance the strength of coloring paper.