Overview
IEC 61249-2-7:2002 is an international standard developed by the International Electrotechnical Commission (IEC) that specifies the requirements for epoxide woven E-glass laminated sheets. These materials are reinforced base materials used for printed boards and other interconnecting structures, featuring defined flammability characteristics based on vertical burning tests. This copper-clad laminated sheet ranges in thickness from 0.05 mm up to 3.2 mm and is engineered to meet stringent electrical and non-electrical property criteria essential for reliable electronic applications.
Key Topics
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Material Composition
The standard defines the use of woven E-glass fibers impregnated with epoxy resin. This combination provides mechanical reinforcement and electrical insulation performance suitable for printed circuit boards (PCBs).
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Flammability Specification
The laminated sheets undergo vertical burning tests to ensure they meet pre-defined flammability ratings, optimizing fire safety compliance for electronics manufacturing.
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Copper Cladding
Copper foil is laminated on one side of the sheet to serve as the conductive layer necessary for circuit patterning, ensuring good adhesion and dimensional stability.
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Mechanical and Electrical Properties
Detailed requirements include laminate thickness, flatness (bow and twist), punching and machining behavior, flexural strength, water absorption, and thermal properties such as glass transition temperature and curing degree.
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Quality Assurance and Conformance
IEC 61249-2-7 outlines the quality management system requirements, responsibilities for inspection, qualification procedures, certificates of conformity, and safety data documentation.
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Marking and Packaging
Internal marking for traceability and durability of packaging for safe transportation and storage are also specified to preserve material integrity.
Applications
This standard is crucial for manufacturers and designers of: