PCB Manufacturing requires a lot of raw materials, including Copper Clad Laminate, Insulated Metal Substrate, Pre-Preg, Copper Foil, Solder Mask Ink, Silkscreen Ink, and some Chemicals. For flexible PCB manufacturing, the raw materials include Polyimide and Polyester Flexible Copper Clad Laminate, Coverlay, Adhesive, EMI film, and sometimes steel sheet or Fr-4 for stiffeners.