Single-sided printed circuit board is in the early 1950s with the advent of the transistor, by the United States as the center of development of products. At that time, the main production methods to direct copper etching method for the mainstream. From 1953 to 1955, Japan for the first time made use of imported copper foil paper phenolic laminate, and a large number of applications in the aspects of radio. In 1956, the Japanese professional circuit board manufacturers, manufacturing technology of single panel and rapid progress. In materials, early in the paper phenolic copper clad laminate based, but because at that time phenolic material electrical insulation is low, poor heat resistance and distortion of welding and other factors, one after another paper ring gas resin, glass fiber epoxy resin material is developed, the consumer electronic machine with single sided boards, almost the paper phenolic substrate plate.
The single panel is in the most basic parts of PCB, focused on one side, the wire is concentrated on the other side. Because the wire appears only in one side, so we call this kind of PCB is called a single panel (Single-sided). Because a single panel on the circuit design has many restrictive (because only one side, wiring can not cross and must walk around alone the path), so only in the early years of the circuit using this kind of board; single panel wiring diagram to network printing (screen printing), i.e. in copper printed on the surface of photoresist, after etching again to prevent solder printed mark. Finally, punching processing completed parts guiding holes and shape. In addition, part of a variety of products, using photographic photosensitive resist pattern forming method.
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