Zhoushan chooses pcb copper foil manufacturers
During the production of copper foil, tiny foreign matters are adhered on the surface to form spots with different colors from the surface, which are called stains. Judgment method: use macroscopic inspection to judge whether it is a waste product, a secondary product or a finished product according to the number and area of stains and the impact on product quality.
Zhoushan chooses pcb copper foil manufacturers
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.
Zhoushan chooses pcb copper foil manufacturers
Excellent tensile strength and elongation High tensile strength and elongation under normal conditions can improve processing ability, enhance rigidity and avoid wrinkles to improve production qualification rate. High temperature extensibility (THE) copper foil and high tensile strength copper foil at high temperature can improve the thermal stability of printed boards and avoid deformation and warpage.
Zhoushan chooses pcb copper foil manufacturers
In order to improve the bonding strength of copper foil to the substrate, oxidation is usually used (that is, after oxidation treatment, a layer of copper oxide or cuprous oxide is formed on the surface, which improves the bonding strength of copper foil and substrate due to the polarity) Or roughen the copper foil (a roughened layer is generated on the surface of the copper foil by electrochemical method, which increases the surface area of the copper foil and improves the bonding strength between the copper foil and the substrate due to the anchoring effect of the roughened layer on the substrate).
Zhoushan chooses pcb copper foil manufacturers
Most copper foils used for domestic printed boards are 35um thick, and 50um copper foils are used as transition products. In high-precision hole metallized double-sided or multilayer board manufacturing, thinner than 35um copper foils, such as 18um, 9um and 5um copper foils, are expected. Some multilayer boards use thicker copper foil, such as 70um.
Zhoushan chooses pcb copper foil manufacturers
Electronic circuit copper foil plays an important role in conducting electricity and heat in printed circuit board (PCB), and is known as the neural network on PCB. At present, copper foil for electronic circuits (PCB copper foil) is divided into two categories, namely conventional copper foil and high-performance copper foil.
