초록 ▼

A drum for copper foil production by an electrodeposition method is composed of an inner support cylinder formed of a copper alloy material having both high electrical conductivity and good elastic properties, and an outer cylinder formed of titanium, zirconium or tantalum having good stripping char

A drum for copper foil production by an electrodeposition method is composed of an inner support cylinder formed of a copper alloy material having both high electrical conductivity and good elastic properties, and an outer cylinder formed of titanium, zirconium or tantalum having good stripping characteristics which has been shrunk fit to the support cylinder. The support cylinder is provided with spaced raised portions. The alloy used to form the support cylinder is also chosen to have a substantially higher coefficient of expansion than titanium, zirconium, or tantalum. As a result of this shrink fitting process, the cylinder of titanium, zirconium or tantalum is biased into intimate contact with the raised portions only of the inner support cylinder. This effectively increases the pressure as, by reducing the interface area, the force per unit area increases. In addition, because the production of copper foil normally involves the use of heated solutions, and because there is heating generated by the large amount of current used in copper foil production, the drum is subjected to a heating and cooling cycle during its normal operation. The differential thermal expansion of the elements of the drum will further secure the inner cylinder to the outer cylinder as the inner cylinder expands to a greater extent than the outer cylinder. This force is also effectively increased by the reduced interface area.

대표청구항 ▼

An improved drum structure of the type having a titanium, zirconium or tantalum stripping surface formed as an outer cylinder of titanium, zirconium or tantalum heat shrunk upon an inner support cylinder, for forming copper foil by electrodeposition onto said stripping surface and subsequent strippi

An improved drum structure of the type having a titanium, zirconium or tantalum stripping surface formed as an outer cylinder of titanium, zirconium or tantalum heat shrunk upon an inner support cylinder, for forming copper foil by electrodeposition onto said stripping surface and subsequent stripping therefrom; comprising: said inner support cylinder being formed with substantially at least the same elastic properties as said outer cylinder and with a substantially higher electrical conductivity and a substantially higher coefficient of thermal expansion than said outer cylinder; said inner cylinder having an outer surface provided with alternating raised portions whereby said raised portions are in intimate contact with said outer cylinder.