ALFRED MASON DENNIS
Pilots at Blue Spruce Dr, Newburgh, IN

5622569, Apr 22, 1997

Jun 2, 1995

8/459926

Alfred M. Dennis - Newburgh IN
Joseph D. Guthrie - Murrysville PA
George T. Gregory - Lower Burrell PA

Aluminum Company of America - Pittsburgh PA

C23G 100, B08B 100, C09K 1302

134 2

A method for cleaning and modifying the surface of aluminum container sheet to make improved food can bodies and/or beverage can ends therefrom. The lowering of magnesium levels on an aluminum oxide surface and through the oxide-metal interface of this sheet, and deposition of at least some phosphorus-containing complex thereon produces container sheet that exhibits improved corrosion performance. The method comprises contacting said container sheet for less than about 20 seconds with a cleaner which preferably includes: about 1. 0-10. 0 wt. % (10. 0-100. 0 g/L) of sodium carbonate; about 0. 1-2. 5 wt. % (1. 0-25. 0 g/L) of sodium hydroxide, said cleaner including a total carbonate and hydroxide concentration in excess of about 3. 0 wt. % (30. 0 g/L); about 0. 1-2. 5 wt. % (1. 0-25. 0 g/L) of sodium gluconate; about 0. 1-2. 0 wt. % (1. 0-20.

6020030, Feb 1, 2000

May 7, 1998

9/074136

Joseph D. Guthrie - Murrysville PA
Alfred M. Dennis - Newburgh IN

Aluminum Company of America - Pittsburgh PA

B05D 136, B05D 138

427345

An aluminum alloy substrate is pretreated with an aqueous solution containing an organophosphorus compound, preferably a vinyiphosphonic acid-acrylic acid copolymer, before coating the substrate with a polymer. Passing the substrate through the solution contaminates it with aluminum and other elements. The pretreatment solution is rejuvenated by removing aluminum with a cation exchange resin that preferably contains a styrene-divinyl benzene copolymer functionalized with sulfonate groups. Rinsing the substrate contaminates the rinse water with the copolymer. The rinse water is concentrated by reverse osmosis or membrane ultrafiltration and returned to the pretreatment solution.