Paper – Mechanical properties (ISO 1924-2, ISO 5626, ISO 1974)
Mechanical properties of paper in the form of tensile testing (ISO 1924-2), tearing resistance (ISO 1974), and folding endurance (ISO 5626) are three measures of paper strength. These methods are important for evaluation in other standards, e.g. the paper permanence (ISO 9706, ISO 11108) and permanence of writing and printing on paper (ISO 11798).
This service is also relevant in: Metrology, Health and life science
Service details
- Service
- Paper – Mechanical properties of paper (TEA ISO 1924-2, Folding Endurance ISO 5626, ISO 1974 Tearing resistance)
- Delivery level
- Accredited
- Standards
ISO 1924-2, Paper and board — Determination of tensile properties - Part 2: Constant rate of elongation method (20 mm/min)
ISO 5626, Paper — Determination of folding endurance
ISO 1974, Paper — Determination of tearing resistance — Elmendorf method
ISO 11798, Information and documentation — Permanence and durability of writing, printing and copying on paper — Requirements and test methods
ISO 9706, Information and documentation — Paper for documents — Requirements for permanence
ISO 11108, Information and documentation — Archival paper — Requirements for permanence and durability
ISO 20494, Paper — Requirements for stability for general graphic applications
- Price
Contact RISE for price information. Please find the contact information below.
Purpose
The purpose of the tests is usually to investigate potential negative impacts on the mechanical strength of the paper after some form of exposure, such as accelerated ageing at elevated temperature and humidity in a climate chamber. The paper’s strength is tested before and after exposure. They can also be used to examine minimum strength requirements for the paper.
Method
Most types of paper, such as fine paper or kraft paper, can be tested according to the standards. Typically, both the machine direction and the cross direction of the paper are tested, as most papers have different strengths in different directions. Testing can be performed on both unaged paper and paper that has been subjected to accelerated ageing in a climate chamber (or other exposure).
Tensile Testing (Tensile Energy Absorption) (ISO 1924-2)
Paper strips are pulled in a tensile tester at a constant pulling speed. The force (N) and elongation (mm) are recorded, and from these parameters, tensile strength (kN/m) and tensile energy absorption (J/m²) are calculated.
Folding Endurance (ISO 5626)
By folding paper strips in a folding tester, the number of double folds is counted. From the double folds, the folding number and folding endurance can be calculated.
Tearing Resistance (ISO 1974)
Tearing resistance indicates the force (mN) required to tear a piece of paper. By tearing paper pieces in a tearing tester, the tearing resistance can be determined.
The standards are important in the following testing:
- Archival durability of writing materials (ISO 11798): Tensile testing and folding endurance
- Archival durability of paper (ISO 11108): Tearing resistance and folding endurance
- Stability of paper (ISO 20494) and permanence of paper (ISO 9706): Tearing resistance
All three tests can, of course, be performed directly on paper, independently of other standards.
All mechanical strength testing of paper is conducted in a controlled climate (23°C and 50% RH).
Accreditation
The testing activities for mechanical properties of paper maintain high quality through accreditation according to SS-EN ISO/IEC 17025:2018.
Delivery
Testing report from an accredited laboratory.