The production of the copper foil for printed circuit boards takes place through deposition and continuous removal of a copper film on a Steel or Titanium roller through electrolysis at high current density of a Copper Sulphate and Sulphuric Acid solution.
In this way you obtain copper foil (Coil) rollers of more than 1 metre in width and of differing lengths of hundreds of metres.
This line is composed of different electrolytic cells, usually baths where the copper Coil is kept scrolling through rollers and is submitted to a further copper deposition in a morphologically different form either of Nickel, Zinc or other treatments to make it suitable to be part of the “wafer” which will be drawn on the printed circuit board.
Both the production line and the treater line use activated Titanium anodes.
The shapes and sizes are very different:
■anodes for the production have a circular sector shape with a radius of around 1.4 m and a width up to 1.3 – 1.4 m. and there are 2 anodes for each cell, to compose a semi-circle.
■anodes for the treater line are flat and with smaller size instead, but which maintain a width that is superior to the width of the coil anyway.
As far as the anodes for the production are concerned, there are three different anode’s drawings:
■Whole radial anode, which is the one described further above and which has a thickness ranging from 12 to 20 mm
■Segmented anode, composed by smaller anodes with the same width but with a height of around 25 cm and thickness of 10 mm, placed side by side to form the two circular sectors of the cell
■Anode with removable panel, which is the most recent technology and is based on the use of 1 mm thick panels, screwed on the base made by a suitably pierced radial anode.
The catalytic coating principle is Iridium Oxide, the Titanium base is opportunely treated with a protective layer that acts as a barrier against the attack of the solution’s high acidity. A particular roughness is created on the Titanium surface to hold the coating more permanently. The coating is subject to very challenging strain both by the current’s high density and by the Lead Oxide’s over-coating which weakens its structure.
Xinxiang Future Hydrochemistry Co., Ltd. offers the recoating service of worn-out anodes and the construction of new anodes for both the process lines, including the cleaning and removal service for the Lead Oxide which is present most of the time and which forms on the production anodes’ surface.