Base materials for printed circuits. Part 3 : Special materials used in connection with printed circuits. First supplement: Specification No. 2: Specification for copper foil for use in the manufacture of copper-clad base materials

This publication serves as the first supplementary amendment to the foundational document IEC 60249-3, established under the framework of the International Electrotechnical Commission. Adopted in the mid-1970s and later brought into effective application in late 2001, it provides essential updates to the original technical specifications. The content focuses on refining the classification and testing procedures for electrical insulation materials, ensuring continued alignment with evolving safety requirements and industry practices. By introducing specific modifications, this supplement addresses emerging technical challenges and clarifies previously ambiguous provisions without altering the core structure of the main standard. It acts as a critical reference for manufacturers, testing laboratories, and regulatory bodies engaged in the evaluation of electrical components, facilitating consistent application of safety measures across international markets. The document ensures that the technical criteria remain relevant and applicable to modern manufacturing processes while maintaining the integrity of the original standard's intent.