“Avangard” Research and Development Company, Podolsk, Russia:

A. I. Zentsov, Head of a Project, e-mail: zentsov@avangardmet.ru

The adhesion of paint and glue coatings is improved as a result of aluminium foil surface`s processing by corona discharge. The adhesion of the surface of aluminum foil depends on the voltage across the electrodes corona, current frequency and duration of the treatment unit area. The obtained data prove that the processing of foil by corona discharge changes radically the properties of the surfase, by increasing its adhesiveness. The higher is the power of corona discharge, more stable are the adhesive properties, both as in an original condition and during the exploitation. With an impact of corona charge energy on the foil surface, almost all contaminations, which prevent a strong connection of surface coatings, are being removed from this surface. The surface becomes active and can be rapidly adsorbed by all impurities and, particularly, the molecules of water from the surrounding atmosphere. This is why the coatings should be immediately applied on the processed foil surface, in contrast to the polymer films. The higher is the period of time between the moment of processing of the foil surface by corona discharge to the moment of the coverings, the higher is the decreasing of the adhesive properties of the foil`s surface. As a result of corona discharge processing of the surface, it is possible to refuse the usage of a primer, during the paint or glue covering on the foil`s surface. This can greatly reduce the cost of finished product. This process is successfully used by a range of manufactures of packaging materials.

1. Metternich W. Aluminiumverarbeitung von konjunkturellen Ausgangsdaten begustigt. Metall. 1986. Vol. 40, No. 10. pp. 1071–1072.
2. Takuji Okugawa, Yoshiyuki Kamimoto. Laminated aluminium foils. Journal of Japan Institute of Light Metals. 1984. Vol. 34, No. 5. pp. 204–300.
3. Klamann D. Smazki i rodstvennye produkty : Sintez. Svoystva. Primenenie. Mezhdunarodnye standarty (Lubricants and relative products : Synthesis. Properties. Application. International standards). Moscow : Khimiya, 1988.
4. Zentsov A. I. Tsvetnye Metally — Non-ferrous metals. 2002. No. 12. pp. 55–57.
5. Zentsov A. I., Brunilin A. I., Gergert A. P., Rutman P. A. Tsvetnye Metally – Non-ferrous metals. 2005. No. 5. pp. 83–86.