Caliper or thickness is an important property of tissue paper and tissue products.
In the tissue industry, thickness-related parameters, such as the roll diameter of rolled products (kitchen towel) or the stack height of folded products (paper towels) are often measured. However, the fact that not only end-use tissue products, but also the base tissue paper from which these products are made, is the subject of trade between companies and countries, means that there is a genuine need for a consistent measure of thickness that can be applied to tissue products at any stage of their manufacture.
Standardized methods of measuring caliper are defined by TAPPI Test Method T 580 pm-12 and ISO 12625-3.