What is CCL PCB material?

The full name of copper-clad laminate is copper-clad laminate, abbreviated as CCL. It is the upstream core material for PCB manufacturing and has a strong interdependence with PCBs.
What is copper clad laminate used for?

A PCB copper clad laminate is a composite material in which one or more layers of copper are laminated to an insulating substrate (usually FR-4).