Water absorbency

The water absorbency of paper can be increased by implementing the following techniques:

1. Increase hydration refining: This involves refining the paper fibers to a greater extent, which improves their ability to absorb water.

2. Consider use of wetting agent: Adding a wetting agent to the paper formulation can enhance its ability to absorb water by reducing surface tension and allowing water to penetrate more easily.

3. Check into possible furnish change: Modifying the composition of the paper’s fiber blend can affect its absorbency. Different types of fibers or additives can be used to achieve the desired water absorbency.

4. Reduce internal and/or surface sizing to improve absorbency: Sizing agents are used in papermaking to control the absorption and repellency of liquids. Reducing the amount of sizing agents can increase the absorbency of the paper.

5. Reduce filler content of sheet if other tests will permit: Fillers such as calcium carbonate or clay are often added to paper to improve its smoothness and opacity. However, these fillers can also reduce water absorbency. Reducing the filler content can enhance the paper’s ability to absorb water.

6. Reduce wet pressing: Wet pressing is a step in papermaking where excess water is removed from the paper sheet. Reducing the intensity or duration of wet pressing can increase the paper’s water absorbency by leaving more water in the sheet.

By applying these techniques, the water absorbency of paper can be improved to meet specific requirements or applications.