VCP copper plating process for flexible printed circuit board

Abstract

The invention provides a VCP copper plating process for a flexible printed circuit board. The VCP copper plating process comprises the following steps of firstly, cleaning a vertical continuous copperplating tank; continuously washing with deionized water, adding the deionized water, copper sulfate pentahydrate, sulfuric acid, hydrochloric acid and a copper-plated additive (polyethylene glycol, sodium polythiodipropionate and Janus Green) into the copper plating tank, starting a circulation filter pump, inputting the to-be-electroplated flexible circuit board into the tank, and starting the current; after electroplating, taking out the circuit board, and cleaning the circuit board with water; and after blow-drying by hot air, transferring the circuit board into a pattern transferring procedure. According to the vertical continuous (VCP) copper plating process for the flexible printed circuit board, after the flexible circuit board is plated copper, the flexibility is stronger and theexpansion shrinkage of the flexible circuit board is smaller, and the deep plating capability of a through hole is higher, so that the bending resistance of the flexible circuit board is greatly improved, the film alignment in subsequent pattern transfer is facilitated, etching of the flexible circuit board with high-density line width / line distance (0.05 mm / 0.05 mm) is more facilitated, the product quality and the product reliability are improved, the production process is pollution-free, and the process is suitable for industrial production.

Description

technical field [0001] The invention belongs to the technical field of flexible printed circuit board processing, and in particular relates to a VCP copper plating process for flexible printed circuit boards. Background technique [0002] With the continuous improvement of high-density circuits, flexible printed circuit boards have higher copper plating ability and ductility, and the requirements for the expansion and contraction of copper-plated boards are also getting higher and higher. The board has the following deficiencies: [0003] 1. The line width / line spacing is mostly 0.075mm / -0.05mm, because the deep plating ability directly has a great impact on the subsequent etching quality. Therefore, the depth capability is poor and the copper plating thickness on the board is large, resulting in high-density line etching. micro short circuit. [0004] 2. The number of bending times of flexible circuit boards is getting higher and higher. Generally, the number of bending t...

AI Technical Summary

Problems solved by technology

[0003] 1. The line width / line spacing is mostly 0.075mm / -0.05mm, because the deep plating ability directly has a great impact on the subsequent etching quality. Therefore, the depth capability is poor and the thickness of copper plating on the board surface is large, resulting in high-density line etching. micro short circuit

[0004] 2. The number of bending times of flexible circuit boards is getting higher and higher. Generally, the number of bending times is between 500,000 and 700,000 times. The poor ductility directly causes the line to break after a large number of bendings, resulting in an open circuit (micro-open circuit) ) seriously affect the signal transmission