2 JOURNAL OF THE SOCIETY OF COSMETIC C_H•E.M_!STS. PROTECTIVE LACQUER SYSTEMS FOR ALUMINIUM CONTAINERS C. E. MORRIS* Presented at the Symposium on "Packaging in the Cosmetic Industry", organised by the Society at Harrogate, Yorks., on $th July 1961. The types o2 corrosion occurring with aluminium containers, the influence o2 production conditions on their corrosion resistance, and the requirements for satis2actory protective systems are discussed. INTRODUCTION The use of coatings for the protection of metals from corrosive influences has long been known. Almost two thousand years ago, Pliny the Eider, described how iron workers used a mixture of white lead, gypsum and pitch for this purpose, whilst today many metals are successfully used in corrosive environments only because they are properly protected by organic or other coatings. This paper is, however, concerned only with protective systems for impact extruded aluminium containers, such as collapsible tubes, rigid and aerosol containers. Tinplate practice falls outside the author's experience, and is in any case, quite different in nearly every respect from the aluminium container industry. Aluminium generally, does not compete directly with tinplate or drawn steel, the main exceptions being in the Scandinavian and Portuguese fish canning fields, also in beer canning in the United States. Similarly, the soft metal side of the tube industry is omitted as it is generally felt that lacquering of tin, tin-coated or lead/lead alloy tubes is technically a poor approach to a packaging problem. Aluminium, under certain conditions, corrodes drastically, from the point of view of its use in packaging. Corrosion, which from a fundamental determination of the life of a set of test pieces would be negligible, can be disastrous when occurring with an aluminium pack. For instance, general surface attack invariably stifles itself very rapidly, and the total weight of metal dissolved may be minute, but in the case of a closed system such as a tube or aerosol container, the volume of hydrogen evolved is sufficient to ruin the pack from every aspect. Similarly, incipient pitting, where in the early stages of attack the cathodic reaction is mainly reduction of oxygen *Universal Metal Products, Ltd., Salford 6, Lanes.

xiv JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS OFFICERS FOR 1962 •..• .... '.-'•.,.• .... 5½½' .., ,. WARREn B. Dr.•xs President . -,.• ß .'• L'' c':'L •.: -..:} "• ....... '•] =•.:- %.. .. :: .%½,. --•v .}• •, :• -- ß • .: -.:•.. RICHARD K. LEH•E Secretary RICHARD E. FAUST Treasurer Administrative Assistant: Anthony Zegarelli, 2 East 63rd St., New York 21, N.Y., Phone: TEmpleton 2-8665 COMMITTEE CHAIRMEN FOR 1962 Advisory: SOPHIE L. PLECHNER) 48 Spring Street, Metuchen, N.J. Arrangements: WALTER W¾SNE, Room 700, 321 West 44th Street, New York 36, N.Y. By-Laws: PAUL G.I. LAVVrER, 9 Ashley Road, Hastings-on-Hud•n, N.Y. Finance: LESTER I. CONRAD, Talmadge Road, Edison, N.J. International Affairs: ROBERT A. KRAMER, 250 East 43rd Street, New York 19, N.Y. Library: FR•NIC J. STEELE, 50 East Putnum Avenue, Greenwich, Conn. Literature Review: ROBERT L. GOLDEMBoeRO) 697 Route 46, Clifton, N.J. Medal Award: RAYMOND E. REED, 456 Merchandise Mart, Chicago 54, Ill. Membership: HARRY ISACOFF, Room 601, 521 West 57th Street, New York 19, N.Y. Nomination: SABBAT J. STRIANSE, 707 Sum- mit Avenue, Union City, N.J. Program: HYMAN HENICIN, 105 Hudson Street, Jersey City 2, N.J. Publications: MAISON G. DENAvARR•, 404 Lothrop Road, Grosse Pointe Farms 36, Mich. Public Relations: EDWARD L. SIL•CIN, 204-15 Foothill Avenue, Hollis 23, L. I., N.Y. Seminar: BARRY M. DASH, 685 Third Avenue, New York 17, N.Y. Special Award: HERMAN E. JAss, 2417 Third Avenue, New York 51, N.Y. Tour Director: SAMUEL COHEN, 160 East 48th Street, New York 17, N.Y.