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印刷运行中的问题与涂布纸张之间的摩擦性能有关,例如印刷中出现的双页进纸。混合涂料中沉淀碳酸钙(PCC)相对于瓷土的比例越高,其动、静态摩擦系数(COFs)越高。这是因为立方形的PCC粒子阻碍了涂布纸张之间滑动,所以与颜料粒子尺寸相关的微观粗糙度影响了摩擦系数。PCC比例较大时,压光会降低COF,但对于完全是瓷土的配方,COF不会改变。添加研磨碳酸钙(GCC)会降低COF;并且对GCC比例较高的配方,提高滑动次数降低动态COF的比率要比PCC比例较高配方的更大。这可能是因为涂布纸张表面突出的部分被选择性压平,这也是GCC比例较高的涂布纸的特征。丁苯胶乳加入量为14%时,COF会降低,当加入量为18%时,静态摩擦系数达到最大值。丁苯胶乳的负面作用仅作用于静态摩擦模式。在所用的润滑剂中,蜡型润滑剂对摩擦系数的降低贡献最大,尤其是对动态摩擦系数。
Problems in the printing run are related to the frictional properties of the coated paper, such as two-fed paper that appears during printing. The higher the ratio of precipitated calcium carbonate (PCC) to china clay in mixed coatings, the higher the kinetic and static friction coefficients (COFs). This is because the cube-shaped PCC particles hinder the sliding between the coated papers, so the micro-roughness related to the size of the pigment particles affects the coefficient of friction. Calendering reduces the COF when the PCC ratio is large, but the COF does not change for recipes completely made of china clay. Adding ground calcium carbonate (GCC) reduces COF; and for higher GCC formulations, increasing the number of glides reduces the dynamic COF ratio more than a higher proportion of PCC formulations. This is probably because the overprinted part of the coated paper surface is selectively flattened, which is also a feature of the coated paper with a higher proportion of GCC. The COF decreased when SBR latex was added at 14%, and the static friction coefficient reached the maximum at 18% SBR. The negative effects of SBR act on the static friction mode only. Among the lubricants used, wax lubricants contribute the most to the reduction of the friction coefficient, especially to the dynamic friction coefficient.