Nanjing Preferred Electronic Copper Foil Processing
With the development of high-density wiring technology for low profile copper foil multilayer boards, the traditional type cannot meet the needs of manufacturing high-precision printed circuit boards. Therefore, a new generation of copper foils, low profile (LP) and ultra-low profile (VLP), have emerged one after another. Compared with ordinary electrolytic copper foil, LP copper foil has fine crystal (2/zm), equiaxed grains, no columnar crystals, lamellar crystals, flat prisms and low surface roughness.
Nanjing Preferred Electronic Copper Foil Processing
Surface passivation: chromate (or chromate and zinc salt) solution is used for surface passivation (i.e. anti oxidation treatment) after the barrier layer is plated to form a complex film with chromium (or chromium zinc) as the main body on the surface, so that the copper foil will not be oxidized and discolored due to direct contact with air, and at the same time, the heat resistance of the copper foil is improved (higher zinc content, better heat resistance), The storage period of copper foil can reach 3 months.
Nanjing Preferred Electronic Copper Foil Processing
Calendered copper foil is the original foil made from copper plate by repeated rolling, and then roughened according to requirements. Due to the limitation of processing technology, its width is difficult to meet the requirements of rigid copper clad laminate, so calendered copper foil is rarely used on rigid copper clad laminate; However, because the bending resistance and elastic coefficient are greater than electrolytic copper foil, they are often used on flexible copper clad laminate.
Nanjing Preferred Electronic Copper Foil Processing
Copper foil is a key conductive material in lithium ion batteries and printed circuit boards. It is a kind of negative electrolytic material, a thin, continuous metal foil deposited on the substrate of circuit board.
Nanjing Preferred Electronic Copper Foil Processing
The calendered copper foil is made by repeated rolling annealing process of copper ingot based on the principle of plastic processing. Its internal structure is lamellar crystal structure, and the product has good ductility. At present, it is mainly used in the production of rigid circuit boards, while the rolled copper foil is mainly used in flexible and high-frequency circuit boards.
Nanjing Preferred Electronic Copper Foil Processing
The production process of electrolytic copper foil is simple. There are three main processes: solution raw foil, surface treatment and product slitting. The production process seems simple, but it is a production process that integrates electronics, machinery and electrochemistry, and is particularly strict with the production environment. Therefore, the industry does not have a set of standard and universal production equipment and technology, and each manufacturer shows its own ingenuity, which is also an important bottleneck affecting the improvement of domestic production capacity and quality. In addition, the different requirements of customers have also resulted in the waste of many intermediate products copper foil in manufacturing. The one-time input-output ratio is even less than 80%, and these copper foils have to be manufactured again, wasting resources.
