How To Improve The Smoothness Of The Paper

Paper machine

The smoothness of paper or paperboard is affected by factors such as fiber form, pulp beating degree, papermaking and felt weaving methods, wet pressure and calendering, filling and coating. Smoothness of the poor paper, after printing may occur the dot printing is not real and virtual phenomenon. So how to improve the smoothness of paper?

Factors that affect paper smoothness

1. Effect of fiber morphology

The effect of fiber morphology on smoothness mainly includes two aspects: one is affected by the degree of fiber fibrillation of various pulp. Fine fibrosis is high, the fiber close integration , smooth is high. On the other hand is the effect of fiber length. Long fiber is not conducive to the improvement of smoothness, because the long fiber is easy to twist to form a gap. And the short fibers are easy to fill with the gap formed by the long fibers, so that the paper has a good smoothness.

2. The impact of the quality of beating

In the same beating conditions, to improve the pulp of the beating degree, the fiber sub-broomized good, can increase the adhesion between the fibers, make the paper surface is more smooth.

3. The quality and amount of the filler, and additives

In the process of papermaking, the fineness of the filling is high and the heterogeneity is low, and the smoothness is high. The more filler is added in the range of strength, the higher the paper smoothness is.

4. The impact of paper machine forming wire and felt performance

With the same number of mesh forming, the more layers, the easier to get a better smoothness.

5. The impact of the slurry uniformity and wire dehydration

In the paper making, the slurry evenly on the wire, full-size quantitative, uniform thickness, then the paper is smooth.

6. The type of press, line pressure and felt replacement cycle

Improve the line pressure, increase the paper tightness, the corresponding smoothness will increase, otherwise it is reduced. If you replace two felt at the same time, especially 1st press paper felt and 3st press felt, because the new felt surface is relatively rough, and directly contact with the paper, have a certain impact on smoothness.

7. The effect of the drying section

The smoothness of the dryer surface has a significant effect on the smoothness of the paper, especially when the sheet enters the dryer, the paper surface is not yet fully shaped, and the smooth surface of the dryer will give the paper a better smoothness. Drying curve is also very important, the paper into the dryer, the temperature should not be too high, otherwise strong drying, loose sheet thickness, smoothness reduced. The appropriate temperature curve, will make the paper fibers evenly and tightly, is conducive to improving the smoothness.

8. The effect of calendering

The quality of the calendering roller, the number of sheets passing through the calendering roller, and the pressing condition of the calendering roller all affect the smoothness of the paper.