History of Insulated Wire

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History of Insulated WireInsulated wire is one of the most important components in electromagnetic devices. Before the insulated wire, physicists had to use various substitute conductors for their experiments. Metal chains, laces soaked in electrolyte and other things could become conductors. However, it was soon discovered that wire was the best conductor. At the same time, insulated wire was necessary for making connections. Especially when building an electromagnetic device. The first insulated wire had textile (silk or cotton) insulation. It was made of thread tightly coiled around a wire. Physicists of the 19th century had to do this tiresome and boring work. For example, the wire used in Henry's experiments was made in this way. By the 70s copper wires were insulated with cotton thread scoured in paraffin. This increased their quality. Thread was coiled around wire in two opposite directions. Later paper insulated wire was invented. It was this type of wire that Morse used to build his telegraph. Paper insulated wire was easier to manufacture but it had certain drawbacks. Compared to silk insulated wire its mechanical strength was lower. It was also thicker and increased the size of the finished device. Gutta-percha insulated wire appeared somewhere in the third quarter of the 19th century. Gutta-percha is a natural ductile material similar to rubber. This type of insulation had some important advantages. It was airproof and protected the wire from oxidation. And it was more durable. However, it was thicker than the insulation made of silk or paper. Combinations of paper, gutta-percha and thread insulation were used to increase durability. This is how the insulation using cord and paper ribbons appeared. Wire was coiled with fibrous twist thread called cord. Several waterproof ribbons made of paper soaked in rubber blood were then coiled over the cord. The next stage was the invention of the enamel insulation at the beginning of the 20th century. The enamel insulation was in fact a 3-12 coat layer of enamel lacquer. After application it was dried and polymerized. Polyvinyl acetate enamel lacquer is the most common type of enamel insulation. After the enamelled wire was invented, it became widespread. Now it is one of the affordable and necessary components of any electronic circuit.