BS EN ISO 12625-12Tissue paper and tissue products -- Part 12: Determination of tensile strength of perforated lines -- Calculation of perforation efficiency
Specifies a test method for the determination of the tensile strength of perforated lines of tissue paper. It uses a tensile-testing apparatus operating with a constant rate of elongation.
This method is only used for measuring machine-direction tensile strength, that is for cross-direction perforations on tissue paper.
The calculation of perforation efficiency is also specified in ISO 12625-12:2010.
Introduction
Tissue papers such as toilet paper and kitchen towel are often pre-cut. They are used after separation of two consecutive sheets.
It is important to know the efficiency of the pre-cut perforations.
The perforation strength should be enough to ensure the product cohesion, but not too high, so that sheets can be easily separated. Depending on the type of tissue product, forces can be applied perpendicular to the perforation lines, or in the direction of the perforation lines.
Scope
ISO 12625-12 Perforation strength specifies a method for the determination of the tensile strength of perforated lines of tissue paper. It uses a tensile-testing apparatus operating with a constant rate of elongation.
This method is only used for measuring machine-direction tensile strength, that is for cross-direction perforations on tissue paper.
The calculation of perforation efficiency is also specified in this part of ISO 12625.
Principle
A perforated test piece of tissue paper or tissue product, of given dimensions, is stretched to break in the machine direction at a constant rate of elongation using a tensile-testing apparatus that measures and records the tensile force as a function of the elongation of the test piece.
From the recorded data, the tensile strength is calculated.
In order to determine the perforation efficiency, measurements are performed both on perforated and non- perforated tissue products.