ISO 5630-5:2008

Overview

ISO 5630-5:2008 - Paper and board - Accelerated ageing - Part 5: Exposure to elevated temperature at 100 °C - specifies a laboratory method to accelerate the ageing of printing and writing papers by exposing conditioned, moist samples to an elevated temperature (100 °C). The standard measures changes in mechanical properties (fold number / folding endurance and tearing resistance) to help predict stability to long‑term natural ageing for cellulose‑based papers (including coated and filled papers).

Key topics and requirements

• Purpose: Predict mechanical stability and long‑term durability of printing and writing papers through accelerated ageing.
• Scope: Applicable to all cellulose‑based printing and writing papers, including coated and filled papers.
• Principle: Conditioned test pieces are sealed in hermetic glass tubes and aged at 100.0 °C ± 1.0 °C; fold number (machine direction) and tearing resistance (cross direction) are compared before and after ageing.
• Apparatus: Forced‑ventilation oven capable of 100 °C ±1 °C; airtight glass tubes with thermally stable caps and O‑rings; accurate balance (0.01 g); cutting and handling tools.
• Sample preparation & loading: Oven‑dry mass per internal tube volume is specified (≈0.0278 g oven‑dry per cm³); example: a 145 cm³ tube should contain ~4.0 g oven‑dry sample. Tubes must be cleaned, dried, conditioned and sealed to ensure airtight ageing.
• Ageing cycle: Typical ageing time is (120 ± 0.5) h. Tubes equilibrate unopened to room temperature before uncapping; samples are re‑conditioned prior to testing.
• Testing & calculations: Use ISO 5626 (folding endurance) and ISO 1974 (Elmendorf tearing resistance). Retention of properties is reported as percentage retention of fold number and tearing resistance.
• Reporting: Include references to standards used, sample identification, conditioning atmosphere, test conditions, measured values, retentions and any deviations.

Applications and users

• Who uses it: Paper manufacturers, quality control and materials testing laboratories, conservators and archival scientists, printers, suppliers of coated and filled papers, and research institutions studying paper permanence.
• Practical uses:
  • Product development and stability screening of new paper grades and coatings
  • Quality control and batch acceptance based on predicted durability
  • Comparative testing for procurement specifications
  • Support for conservation decisions and archival material selection
• Limitations: ISO 5630‑5 evaluates mechanical stability under a specific accelerated thermal regime. For comprehensive permanence assessment, combine this method with other accelerated ageing tests (moist heat, dry heat, atmospheric pollutants) as recommended in ISO 5630 introduction.

Related standards

• ISO 5630 series (Parts 1, 3, 4, 5, 6)
• ISO 186 (sampling), ISO 187 (conditioning), ISO 638 (dry matter), ISO 1974 (tearing resistance), ISO 5626 (folding endurance)