● Fiber-glass Cloth
● Epoxy Resins
● Copper Foils
The materials needed for the manufacture of laminates are glass fabric (filler), epoxies (resin), solvent and copper foil.
1. Fiber-glass Cloth
Glass cloth acts as the main structural reinforcement in manufacture of laminates. The rigidity and strength offered by glass compliments the binding, encapsulating and insulative properties of the epoxy resin.
2. Epoxy Resins
The function of the resin is to act as a “glue” to hold the laminate together. Epoxy resins can be purchased from various vendors at various steps of PCB manufacture. Epoxy resin can be had in a liquid form so that it can be concocted to upstaged resin using proprietary recipes and processes. It can also be purchased in the advanced or upstaged state, wherein the solid resin, complete with hardness and catalysts, is ready for use in treating.
3. Copper Foils
Most foils used in FR-4 manufacture are electrodeposited type foils. These are manufactured by plating copper onto slowly revolving drum-shaped cathodes that are partially immersed in the plating solution. As the drum revolves, the plated copper deposit is removed from the cathode drum at one continuous speed. Varying the drum speed and current density helps to vary the copper deposit and consequently, the resulting foil thickness. In addition, the foil is coated with a micro-thin film of protective coating to prevent oxidation of the copper during lamination and storage.