You may always hear about core and prepreg in PCB production. 

The material is composed of copper foil, reinforcement, resin matrix, and filler system. And each part plays a key role.

The appropriate materials have a good quality assurance for the products that produced, but it's not that the more expensive the material is, the more suitable it is for your products.

Please kindly contact us KnownPCB, we can provide a variety of material for your better choice.