Overview
IEC 62899-302-4:2024 - Printed electronics, Part 302-4 - defines measurement methods and specifications for a medium used to evaluate inkjet dot placement in printed electronics. The standard describes what constitutes an appropriate medium (a substrate with functional layers such as a liquid-absorbing coating or a hydrophilic/hydrophobic layer) and provides parameter definitions, environmental conditions, and measurement methods to ensure actual inkjet dot placement is recorded reliably.
Key topics and technical requirements
- Definition of medium: a substrate plus functional layer(s) to facilitate ink pinning (liquid absorbing layer or hydrophilic/hydrophobic layer). Substrates may include glass, metal foil, silicon wafer, plastic film or paper if they do not alter print-head-to-medium geometry.
- Parameters and measurement methods (outlined in the standard):
- Size and dimensional stability
- Thermal dependency (coefficient of linear thermal expansion)
- Humidity dependency (hygroexpansivity)
- Thickness and flatness (curl)
- Smoothness / surface roughness
- Liquid absorption capacity
- Surface wettability (hydrophilic vs hydrophobic behavior)
- Roundness of dot mark (including after drying)
- Capability to render dot marks for transparent inks
- Stability of dropped position between printing and measurement
- Coating characteristics
- Environmental conditions for measurement: recommended baseline conditions are (23 ± 1) °C and (50 ± 5) % RH; air pressure should be reported.
- Ink handling guidance: to avoid print-head contamination the standard assumes measurement inks are the same as production inks or a compatible solvent-only substitute by agreement; users must note any deviations because ink chemistry affects dot placement.
- Reporting: measurement procedures and any deviations from actual production conditions must be recorded.
Applications and users
IEC 62899-302-4 is practical for:
- Printed-electronics OEMs and integrators validating inkjet placement accuracy for circuits, sensors, antennas and flexible electronics.
- Ink and coating manufacturers developing media formulations (absorbing layers, wettability treatments).
- Inkjet equipment manufacturers and calibration labs performing dot placement verification and quality control.
- R&D teams and test houses establishing repeatable measurement protocols for process qualification.
Using this standard helps ensure reproducible dot-placement evaluation, reduce process variability, and speed development of reliable printed-electronic devices.
Related standards
Normative references include relevant ISO standards on paper sizing, thickness, surface texture, hygroexpansivity and thermal expansion (e.g., ISO 216, ISO 534, ISO 4287, ISO 8226-1/-2, ISO 11359-2, ISO 18910).
Keywords: IEC 62899-302-4:2024, printed electronics, inkjet dot placement, medium for inkjet printing, dot placement evaluation, surface wettability, liquid absorption, hygroexpansivity.