What is Kinds of FR4 Prototype PCB Product Dry Film?

PCB dry film is a polymer compound, which produces a polymerization reaction after ultraviolet irradiation, forming a stable substance attached to the board surface, thereby achieving the function of blocking electroplating and etching. What are the types of fr4 circuit board dry film? 1. Single-sided PCB Board The substrate material is mainly paper phenol (phenol)…