Beverage Can Ends and its Opening Devices

Although the position of beverage cans have been threatened by HDPE (high-density polyethylene) and PET (polyethylene terephthalate) bottles, advancements in packaging technology have seen the introduction of improved functional features, a major factor for growth in the beverage end-use sector.

Two holes made with a church key

The early metal beverage can was made out of steel and had no pull-tab. The can was opened by punching two triangular holes in the lid – a large one for drinking, and a small one to admit air. For punching the holes often a so called church-key was used. As early as 1936, inventors were applying for patents on self-opening can designs, but the technology of the time made these inventions impractical. Later advancements saw the ends of the can made out of aluminium instead of steel.

Pull-tab
In 1956 Mikola Kondakow of Thunder Bay, Ontario, Canada, invented the pull tab version for bottles (Canadian patent 476789). Then, in 1962, Ermal Cleon Fraze of Dayton, Ohio, invented a similar integral rivet and pull-tab version for cans (also known in British English as ring pull), which had a ring attached at the rivet for pulling, and which would come off completely to be discarded. He received U.S. Patent No. 3,349,949 for his pull-tab can design in 1963 and licensed his invention to Alcoa and Pittsburgh Brewing Company. The latter introduced the design on its Iron City Beer cans.
The pull-tab got a lot of critics as it littered the roadside and caused injuries due to the very sharp edges of discarded tabs on beaches and in parks.

Stay-on-tab
The pull-tabs were eventually replaced almost exclusively by the stay-on-tabs we still use today. Stay-on-tabs (also called colon tabs) were invented by Daniel F. Cudzik of Reynolds Metals in Richmond, Virginia, in 1975.
The mechanism uses a separate tab attached to the upper surface as a lever to depress a scored part of the lid, which folds underneath the top of the can and out of the way of the resulting opening. This design reduced injuries and reduced roadside litter caused by the removable tabs.

Beverages began using this new type of tab in the United States by 1977. Such “retained ring-pull” cans supplanted pull-off tabs in the United Kingdom in 1989 for soft drinks.

Top end or lid
To support the mechanism of the tabs, the lid is made of a slightly different alloy than the aluminium for the base and sides of the can. The inward bulge of the bottom of the can helps it withstand the pressure exerted by the liquid inside it, but the flat lid must be stiffer and stronger than the base, so it is made of an aluminium with more magnesium and less manganese than the rest of the can. This results in stronger metal, and the lid is considerably thicker than the walls.

The centre of the lid is stretched upward slightly and drawn to form a rivet. The tab, a separate piece of metal, is inserted under the rivet and secured by it. Then the lid is scored so that when the tab is pulled by the consumer, the metal will detach easily and leave the proper opening.

And that’s roughly the situation we still have. Over the years since the introduction of the stay-on-tab only minor modifications have been seen. Let’s have a look at the most recent and significant ones.

In a busy, saturated market, it is sometimes the seemingly simplest changes to a package that can make a difference. From the moment consumers started to drink straight from the can, there have been two complaints.

The first of course is the restricted flow of liquid and the “glugging”, the second is the effect of stilling of the beverage after a can is opened and not emptied at once.
Over the last years we have seen some innovations to answer these consumer complaints.

Vented Wide Mouth Can and the Punch Top Can
Coors is a company known historically for taking innovative leaps with its cans. In 2008 Coors Light launched of its new Vented Wide Mouth Can. The modified, so called SmoothPour End features a large opening and a vent tube which directs airflow into the can.
With the industry’s first built-in embossed vent (outlined in blue in photo) and a new 8% wider opening, the Vented Wide Mouth Can allows for a smoother pour and intends to deliver a draft-like experience that reduces the vacuum or “glugging” effect. All 12-oz Coors Light and Coors Banquet cans feature the Vented Wide Mouth Can.
The wide-mouth end itself was introduced in 2006 and is 27% wider than the largest opening found on competing brands of domestic light beer.
Ball Corp. in Broomfield, CO, produces the Vented Wide Mouth Cans exclusively for Coors based on design originally developed by Alcoa in Pittsburgh, PA.

To complete the overview of the improvements of pouring launched by the MillerCoors Breweries we have to include the Punch Top Can recently launched for Miller Lite.

Miller Lite and Miller Genuine Draft 12oz and 16oz varieties are now packaged in the Punch Top Can, where the innovation involves consumers piercing an additional hole in the top to increase airflow, with the company promising a smoother pour.

The beer can has a small indentation that when punched in results in a hole that admits air. Unlike the pull tab, the punch-top indentation does not have a built-in means of activation, therefore, the consumer has to use a tool, such as a house key or a pen.

But the best solution to create a draft-like experience and reduce the vacuum or “glugging” effect came from SABMiller during the World Football Cup in South Africa.

SABMiller’s Castle Can
South African Breweries Ltd., SABMiller’s subsidiary in South Africa, introduced a can with a full-aperture end for the World Cup tournament. It’s recyclable, and it transforms the can into a convenient drinking cup.

This advancement, which Crown Holdings Inc. developed, enables consumers to remove the lid, thereby transforming the can into a drinking cup. The can’s purpose is to reduce lines at bars around events by shortening serving time, removing the need for glassware and draught installations, but without compromising on the drinking experience.
The new full aperture end provides an interesting alternative to traditional cans and glass bottles that are typically prohibited at stadiums and arenas around the world.

Budweiser Gan Bei Can with full aperture

Just last week Anheuser-Busch InBev launched in China its Budweiser in premium metal packaging featuring a full aperture end. Branded the 360 End, the innovation is identical as written above for SABMiller and allows the entire can lid to be removed, turning the can itself into a drinking cup. “The ‘gan bei’ can, developed by Crown, is a brand new product with a very specific goal: enhancing the drinking experience for Budweiser consumers.
The 360 End is produced using a combination of Crown’s food can and beverage can technology.

I think it is a brilliant idea and a very interesting development, I have one objection. One of the reasons the Stay-on Tab was developed as replacement for the Ring-pull Tap was the Ring-pull Tap littering beaches and events. I am wondering what happens with all the (sharp-edged) lids after entirely removed from the can. Are people in these days more aware of the environment and willing to use the trash bin to drop the lid into? I am afraid not, as human beings are notorious polluters.

The second consumer wish is the reclosability of the can or at least a covering of the opening to protect the content. We will talk about reclosability solutions in the next article.