IEC 62899-202-6:2020

Overview

IEC 62899-202-6:2020 is an international standard in the Printed Electronics series that defines an in‑situ measurement method for resistance changes of a printed conductive layer on a flexible substrate when exposed to high temperature and humidity. It specifies sample shapes, environmental test conditions, measurement jigs (two‑wire and four‑wire), and data reporting requirements to evaluate environmental stability of conductive inks and printed conductive films.

Key Topics and Requirements

• Scope and purpose
  • Method to measure resistance change of conductive layers made by printing methods on flexible substrates under controlled temperature and humidity.
• Test samples
  • Recommended rectangular samples with a long:short ratio ≥ 20 (example size: 200 mm × 10 mm). Dimensional tolerance ±5%.
• Environmental test conditions
  • Standard humidity/temperature condition: 85 °C ±2 °C and 85 % RH ±5 % (unless otherwise specified).
  • High temperature testing generally at 120 °C ±2 °C, but limited to 15 °C below the substrate glass transition temperature (Tg) if Tg < 120 °C.
  • Thermal cycling defined (e.g., −20 °C ↔ 80 °C cycles) with specified dwell and ramp times; humidity typically held at ~50 % RH.
• Test method and apparatus
  • In‑chamber, in‑situ resistance monitoring using two‑wire or four‑wire connections; fixtures may include rigid plates and screws or metal grips to ensure stable contact.
  • Guidance on measurement intervals and applied currents is provided (see referenced tables in the standard).
• Data analysis and reporting
  • Procedures for recording resistance change over time, reporting electrical properties, and presenting test results for reliability assessment.

Applications and Users

• Intended for stakeholders in printed electronics, including:
  • Conductive ink and material manufacturers validating environmental stability.
  • Flexible device designers and OEMs (e.g., wearables, flexible displays, touch panels, smart packaging) requiring reliable printed interconnects or electrodes.
  • Test laboratories and quality assurance teams performing environmental reliability testing.
• Practical uses:
  • Compare formulation performance (e.g., silver/copper nanowire inks, metal meshes) under accelerated ageing.
  • Define storage/handling recommendations and acceptance criteria for printed conductive films.
  • Support material selection and lifetime predictions for flexible electronic products.

Related Standards

• IEC 62899-201 - Printed electronics: Materials - Substrates
• IEC 62899-202 - Printed electronics: Materials - Conductive ink
• IEC 62899-202-5 - Mechanical bending test for printed conductive layers

Keywords: IEC 62899-202-6:2020, printed electronics, conductive ink, resistance measurement, high temperature humidity, flexible substrate, environmental test, in-situ measurement.