Significant Factors That Affect Paper Stiffness

 The stiffness of a paper indicates its ability to withstand bending. It explains the paper's tendency to return to its original shape and form after a force is applied to it. Generally, the stiffness of a paper depends significantly upon the thickness of the sheet of paper. However, there are other factors too that determine this property. Whatever the factor, manufacturers can easily test the stiffness using a stiffness tester for paper. Let us jump to the following section to learn about them.

Significant Factors That Affect Paper Stiffness

1. Thickness

The thickness can be a single sheet thickness, bulk thickness, or structural thickness. It measures the distance between the two surfaces of the paper sheet. Thickness plays a significant role in changing the stiffness of the paper. With a change in thickness, a paper’s stiffness can be directly changed. Hence, if the thickness of the paper is doubled, the stiffness will increase too by almost 5.5 times. 

2. Restraint At the time of Drying

Restraint at the time of drying is defined as the linear change in the dimension that a wet web undergoes as and when it dries to equilibrium weight at 50% relative humidity. By controlling stiffness by restraint during drying, a large amount of stiffness can be increased.

 

3. Orientation of Fiber

Another factor that can increase the stiffness of the paper is fiber orientation. By changing the orientation, the stiffness of the paper can be easily and inexpensively increased. 

Conclusion

Besides the above factors, moisture content, temperature, interfiber bonding, specific gravity, and resin additives are other factors that determine the stiffness of the paper. To gain maximum stiffness, manufacturers need to understand these factors in-depth. Only then they are able to evaluate the stiffness using apt machines such as a Taber stiffness tester. Get in touch with UEC to invest in them.