Overview
ISO 9958-2:1992 specifies standardized test methods for evaluating the properties of draughting film with a polyester (biaxially oriented polyethylene terephthalate) base used as a medium for drawn and written technical information that must be duplicated, revised and stored. It is Part 2 of the ISO 9958 series (Part 1 covers requirements and marking) and focuses on laboratory procedures to determine physical, surface and imaging performance characteristics.
Key topics and technical requirements
The standard details test procedures and measurement conditions, including conditioning at (23 ± 2) °C and (50 ± 5) % RH, for the following properties:
- Dimensional stability and permanent dimensional change
- Measurements in machine and cross directions; guidance references ISO 6221 for thermal/hygroscopic expansion tests.
- Stability of form
- Tests for curling and bulging (curl measurement on A4 sheets; unrolling/inspection after temperature/humidity cycling).
- Tape stripping adhesion
- Application and rapid removal of pressure-sensitive tape; target peel forces typically referenced as 3–4 N per 10 mm of tape width; includes adhesion after immersion in water and after exposure to 25% ammonia.
- Susceptibility to fold marks
- Creation of a controlled fold under a specified pressure (approx. 2.5 N ± 0.1 N) and evaluation by copying and visual inspection.
- Surface resistance
- Measured per IEC 93 methods for volume and surface resistivity.
- Visual density and visual density after heat ageing
- Density measured with densitometers per ISO 5-2 / ISO 5-3; heat-ageing procedure (forced-air oven at 100 ± 2 °C for 16 h) and post-ageing density checks.
- Draughting and redraughting quality
- Line width and continuity tests using tubular technical pens and mechanical pencils (references ISO 9175, ISO 9177); redraughting checks include erasure and redraw cycles with subsequent microscopic measurement.
Practical applications and users
ISO 9958-2 is used by:
- Manufacturers and suppliers of polyester draughting film for product verification and quality control.
- Materials and testing laboratories performing conformance testing and comparative evaluations.
- Technical drawing and archival professionals ensuring media will retain dimensional, surface and imaging integrity during use, duplication and storage.
- Procurement and quality assurance teams specifying film performance for engineering drawing, reprographics and long-term record keeping.
Adopting these test methods helps ensure reliable, reproducible assessments of film performance for applications where stability, erasability, adhesion and image quality are critical.
Related standards
Keywords: ISO 9958-2:1992, draughting film, polyester base, dimensional stability, tape stripping adhesion, visual density, draughting quality, test methods.
