Historically, the Joint Industry Standard (J-STD) governed these materials. However, to streamline standards and maintain better control over updates, the industry transitioned the content fully under the IPC umbrella. IPC-4562 is now the sole governing standard for flexible base dielectrics in North America and is widely accepted globally.
The standard divides materials into three functional classes: General electronic products (consumer goods). ipc-4562 pdf
When your receiving dock unloads a roll of copper foil, your QC team should use IPC-4562 to verify: ipc-4562 pdf