Six boards illustrating the stages of manufacture of a Printed Circuit Board. Printed circuit boards (PCBs) have been an important factor in the development of mass production methods in the electronics industries. A typical PCB is made by taking a phenolic resin paper laminate which has a copper layer on the surface, printing the circuit design on the copper, and then etching away the copper not protected by the printing ink using a solution of ferric chloride. These PCBs were made by GSPK Circuits Ltd.