Overview
EN ISO 12625-4:2022 specifies a laboratory test method for determining the tensile strength, stretch at maximum force, and tensile energy absorption (TEA) of tissue paper and tissue products. The procedure uses a tensile-testing apparatus operating with a constant rate of elongation and defines how to calculate the tensile index and tensile energy absorption index. This third edition (2022) supersedes the 2016 version and incorporates an optional Annex B for determining tensile modulus.
Key topics and technical requirements
- Test principle: Stretch a prepared test piece to break while recording tensile force versus elongation; calculate strength, stretch and energy from the resulting curve.
- Apparatus: A constant-rate-of-elongation tensile tester compliant with ISO 1924-2 and verified per ISO 7500-1. Includes appropriate clamps, means for measuring the area under the force–elongation curve, and a cutting device for preparing specimens.
- Conditioning and sampling: Specimens must be conditioned in a standard atmosphere (see ISO 187) and sampled according to ISO 186 to determine representative quality.
- Specimen preparation: Defined dimensions, number of test pieces and handling to ensure reproducible results.
- Measurement details:
- Tensile strength: Maximum tensile force per unit width at break.
- Stretch at maximum force: Elongation at the instant of maximum force (expressed as % of initial span); method uses slack correction and begins measuring elongation after a small pre-load (document notes a start threshold of (0.25 ± 0.05) N).
- Tensile energy absorption (TEA): Energy absorbed per unit surface area up to the onset of break; TEA index is TEA divided by grammage.
- Calculations and reporting: Standard formulas for tensile index (strength/grammage) and TEA index, plus required test report elements. Precision data and optional tensile modulus method are included in Annex A and B respectively.
Applications and users
- Quality control and specification of tissue paper, toilet tissue, facial tissues, kitchen towels and related tissue products.
- Product development and R&D teams assessing strength vs softness trade-offs.
- Laboratory testing services and in-house QC labs verifying batch consistency and supplier claims.
- Procurement and compliance professionals using standardized test data for supplier agreements and regulatory documentation.
Related standards
- ISO 1924-2 - Determination of tensile properties (constant rate of elongation)
- ISO 186 - Sampling to determine average quality
- ISO 187 - Standard atmosphere for conditioning and testing
- ISO 7500-1 - Calibration of tensile testing machines
- ISO 12625-1 - Vocabulary for tissue paper
- ISO 12625-6 - Determination of grammage
Keywords: EN ISO 12625-4:2022, tissue paper tensile strength test, tensile energy absorption, tensile index, stretch at maximum force, constant rate of elongation, ISO 1924-2, tensile modulus.
