Packaging beverage-can

The primary and secondary aluminum industry produces ingots of pure (greater than 99%) aluminum that serve as feedstock for other materials and processes. Within the U.S., the leading end-users of aluminum come from three industries containers and packaging, transportation, and building and construction. Examples of materials produced with aluminum are sheet metal aluminum plate and foil rod, bar, and wire beverage cans automobiles aircraft components and window/door frames. 

Since beverage cans, particularly two-piece cans, are made with very thin side walls, their ability to resist vertical top loads is limited. It is not until they have been filled with carbonated product and the product has reached room temperature that cans achieve full top-load strength. For non-carbonated products this can be a problem however, there are systems available which can inject a precise volume of liquid nitrogen into a filled can, just before the end is seamed on to the can body. As the liquid converts to a gaseous state, it expands. This helps to expel excess oxygen from the headspace, which may otherwise affect shelf life, and provides the internal pressure required for side-wall strength and package stability. 

Claire Jenkins, Dir.-Corp. Affairs David Robbie, Dir.-Finance Malcolm Harrison, Dir.-Plastic Packaging Andre Balbi, Dir.-Beverage Can, Americas lain Percival, Dir.-Enterprise Risk Peter Ellwood, Chmn. 

Major uses of aluminum are in transportation (37% of US consumption in 2000), packaging, including beverage cans (22%), and building (15%). 

The thickness of the ink or paint on the metal is important. Not enough beam is absorbed if the coating is too thin. For example, on most beverage cans, the ink is so thin that an acceptable contrast is not achieved. On the other hand, aluminum foil pouches used in pharmaceutical and food packaging are coated with paper and/or ink to produce good contrast when coded with the laser. 

One of the first fluids tried as a lubricant on these chains was water and the formulations used in the industry today are still 99% water-based. A conveyor lubricant formulation concentrate contains 5-20% active lubricant which is diluted 1 100 on site. This dilute product is combined with water at low levels and sprayed through nozzles on to the conveyor belt or chain. The active lubricant component is consequently usually less than 1 mg/1 when in final use at the food or beverage processing plant. A packaging plant can use up to 40 gallons of lubricant per hour and this places extreme demands on the products cost/performance and environmental profile. 

Furthermore, the clarity/transparency of PET/clay nanocomposites is also one of the most important issues for some applications, such as packaging, beverage bottles, etc. It is noted that the transparency can be maintained at a clay content of less than 2 wt% (see Table 5.2). At the mean time, reasonable barrier properties (CO2 and UV) are achieved. This demonstrates that a balance could be achieved between clarity and good barrier properties for these nanocomposites. 

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