Overview
IEC 61249-2-26:2005 specifies international requirements for non-halogenated epoxide reinforced base materials used in printed circuit boards (PCBs) and other interconnecting structures. This standard focuses on non-woven/woven E-glass reinforced laminated sheets, copper-clad and of defined flammability, tested by vertical burning methods. The materials covered range in thickness from 0.80 mm to 1.60 mm and emphasize environmentally friendly, flame-retardant properties achieved without halogenated compounds. The glass transition temperature (Tg) must be at least 95 °C to ensure thermal stability in electronic applications.
Key Topics
- Material Composition: Specifies resin systems using non-halogenated epoxide and inorganic/organic fire retardants integrated within the polymer matrix or as additives. Reinforcement consists of E-glass fibers, supplied as woven or non-woven fabrics.
- Flammability Requirements: Defines performance criteria based on vertical burning tests that ensure fire safety without relying on halogenated flame retardants.
- Copper Cladding: Standards for laminated sheets with copper foil that meet adhesion, thickness, and electrical property specifications critical to PCB reliability.
- Electrical and Mechanical Properties: Defines minimum electrical insulation, flexural strength, dimensional stability, and resistance to moisture absorption.
- Quality Assurance: Covers manufacturing quality systems, inspection protocols, qualification controls, and certification to ensure materials meet specification during production.
- Marking and Packaging: Requirements for internal marking to identify batch and material, as well as packaging methods to maintain product integrity.
Applications
The IEC 61249-2-26 standard is essential for manufacturers, designers, and quality engineers involved in:
- Printed Circuit Board Fabrication: Providing environmentally sustainable, flame-retardant base materials with consistent mechanical and electrical characteristics.
- High-Reliability Electronics: Used in automotive, industrial, and telecommunications sectors where fire safety and material stability under thermal stress are priorities.
- Interconnecting Structures: Beyond PCBs, suitable for multilayer laminates and substrates used in complex electronic assemblies.
- Compliance and Procurement: Ensures suppliers provide materials that meet international fire, electrical, and mechanical performance standards required for global market access.
Related Standards
- IEC 61249 Series: Covers various reinforced base materials and laminated sheets for printed boards, addressing halogenated and non-halogenated epoxy systems.
- UL 94: For flammability classification of plastics used in devices and appliances, complementary to vertical burning tests in IEC 61249-2-26.
- IPC Standards: Provide guidelines on PCB fabrication processes where materials specified in IEC 61249-2-26 are applied.
- RoHS Directive: Supports the use of non-halogenated materials to comply with hazardous substance regulations in electronics.
- IEC 60034-1: Sample of IEC standards renumbered in the 60000-series, illustrating international harmonization of electrotechnical standards.
Keywords: IEC 61249-2-26, non-halogenated epoxide, E-glass reinforced laminate, printed circuit board materials, copper-clad laminates, flame retardant PCB materials, vertical burning test, glass transition temperature, electrical insulation, PCB substrate standards, fire safety electronics, environmental compliance materials.
Open preview (PDF)Materials for printed boards and other interconnecting structures - Part 2-26: Reinforced base materials clad and unclad - Non-halogenated epoxide non-woven/woven E-glass reinforced laminated sheets of defined flammability (vertical burning test), copper-clad
