Electronic assembly wire and flat cable comprising same

Abstract

The invention discloses a conductor of electronic part, which comprises the following parts: conductive base (1), Sn alloy coating layer (2) with Sn and Bi, Cu, Ag or Sn and Zn on the positive layer of conductive base (1), upper coating layer (3) with Zn coating layer, Ag coating layer, SnZn alloy coating layer, SnAg alloy coating layer or SnBi alloy coating layer on the surface of Sn alloy coating layer (2), wherein the density of Bi, Cu, Ag or Zn is 0.1-15%; the total thickness of Sn alloy coating layer (2) and upper coating layer (3) is 0.5-20 mum.

Description

technical field The present invention relates to a lead wire for electronic components and a flat cable using the lead wire. More specifically, the present invention relates to lead wires and flat cables for electronic components that do not use toxic lead and have an effect of preventing short-circuit causes. Background technique Sn (tin) plating is widely used as a protective film for improving solderability or a protective film for an anti-corrosion coating in parts for weak current industries, parts for electronic industries, and the like. It is known that whiskers (whiskers) occur in Sn (tin) plating, and for example, in flexible flat cables in which the intervals between flat cables are extremely small, the whiskers may cause short circuits. As measures to prevent this short circuit, there are methods of performing heat treatment such as annealing treatment, and replacing the Sn plating with another plating protection film such as gold plating or SnPb alloy plating....

AI Technical Summary

Problems solved by technology

However, it is not possible to sufficiently prevent the generation of whiskers by only performing such conventional heat treatment.

Furthermore, gold plating and the like do not generate whiskers, but the cost is too high, and SnPb alloy plating is not preferable from the viewpoint of environmental protection because lead is used.

Therefore, in recent years, SnBi (bismuth) alloy plating is attracting people's attention (for example, referring to Patent Document 1), but it is still not enough to prevent whiskers from occurring.

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