How many of us are fighting to open the screw cap of a glass jar. Am I the only one with rheumatic fingers and no power anymore in my hands? No, I am not. It is a general complaint of consumers in regard to glass jars. And the processed food industry or the glass industry for their part? Well, they think they can get away with it, by letting their costumers buy a Black&Decker or any other fancy jar opener or use some ridiculous manual tool to punch a hole in the cap.
Haven’t there been any developments for easier screw caps for jars? There have been. When you search the international patents database you find various, some simple, some complicated. But no one ever reached the market commercially. Yes, I know an easy-open screw cap is probably more expensive and that seems to be the bottle-neck. However some see signs that the glass jar for processed food may be experiencing a large decline in market share from the growth in use of PET-jars, paperboard cartons and flexible stand-up pouches.
Furthermore it goes without discussion that consumers are still focused on convenience and that by showing just a little bit more creativity and innovation, an additional small feature to a product might actually attract much more consumers to buy the product.
We should learn, at times, to focus on the finer details of product presentation.
One of these small additions is the “Abre-Fácil“(Portuguese for easy-open) screw cap for glass jars. Metalgráfica Rojek Ltda, a Brazilian company specialized in the production of metal packages for food products, is the original inventor of the “Abre-Fácil” screw cap.
We all know that the reason a screw cap of a glass jar is only to open using force, is due to vacuum inside the jar. The products are hot filled and after cooling the free space in the top of the jar has drawn a vacuum keeping the screw cap closely fixed to the glass rim of the jar and in this way securing the shelf-life and integrity of the product. That’s why we punch a hole in the cap to eliminate the vacuum, so that the cap can be screwed off.
This principle (eliminating the vacuum condition) Rojek used for its “Abre-Fácil” caps.
The screw cap, made from steel, has a small round protection seal, made from polypropylene, in the centre of the lid. By lifting this PP-dot, air is allowed to enter the container, which facilitates the rotation of the screw cap. As it is a screw cap, the jar can be re-closed and re-sealed after opening, allowing gradual consumption.
Yes, it is that simple, although to manufacture the screw caps is a bit more complicated. To make the special lid, a metal disc is formed into a screw cap and a hole is punched into the centre before a dot of polypropylene is applied to the hole on one side. The lid is then flipped over, and a very small dot of polypropylene is applied to the underside, which bonds both ‘dots’ together, creating something like a double flanged seal.
The one covering the hole on the outside must adhere reliably yet still be peelable when the consumer needs to break the internal vacuum and open the jar. As for the polypropylene over the hole on the inside (bottom side) of the cap, it has to bond to the polypropylene on the opposite side of the hole so that when the consumer peels the outside PP-dot off, the inside compound will come away to release the internal vacuum.
The seal can’t be removed completely: even after lifting, a small part of the PP-dot remains glued to the cap. This allows the air-inlet to be covered again after the loss of vacuum, increasing the protection of foods that are not consumed.
Is this a new packaging invention? No, not really. You will be shocked to know that the “Abre-Fácil” technology has been present in the Brazilian market since 1989. I present it here today, as Rojek has perfected the “Abre-Fácil” for glass jars and re-introduced it for the range of palmitos of Gini, baptizing the screw cap “BR-1”.
To complete the story Rojek also manufactures cans with an “Abre-Fácil” lid. Very popular in Brazil, among others with various products of Nestlé, many tomato sauces and chocolate creams.
And (as far as I know) only once used in the USA (in Europe I never saw them) with a steel food can by Hirzel Canning Co. for its Dei Fratelli Pizza Sauce and Italian Dip. An easy-to-open, reclosable, 12-oz steel can that used, what Silgan Containers called, Dot-Top technology. Silgan licensed the technology from Metalgrafica Rojek Ltda, the original Brazilian inventor as described above.
The construction of the can lid or can end is similar to the screw cap of the glass jar. The lid of the can has a central vent hole sealed using a plastic plug. Once the seal is broken, the internal vacuum formed during the sterilization process is released by removing the plug and the end can be taken off. An additional benefit is that the end has a unique re-closable feature. Imagine a re-closable can. No can opener needed.