Why does every beer bottle cap have 21 aliases?

Beer is a great beverage for the summer, and is an integral part of many parties. But maybe not everyone knows interesting information related to jagged beer caps.

Origin of jagged bottle caps

On 2/2/1892, the bottling industry was forever changed thanks to the appearance of the crown cap (the type of metal beer bottle cap we often see today). This great idea belongs to William Painter , an American inventor. His entire life had more than 80 inventions, but the creation of the metal bottle cap was the most successful invention and quickly "transformed" Painter into a rich man.

Types of bottle caps.

In the 1880s, there were more and more carbonated soft drinks on the market and they were very popular. But the transportation of this beverage has many difficulties because cork made of cork, porcelain or metal does not guarantee the tightness leading to gas loss and the quality of beverage is significantly affected. .

Determined to prevent this phenomenon, Painter invented a bottle cap called Crown Cork. The new bottle cap has a wavy border and an inner liner to prevent liquid from coming into contact with the metal plate.

After working with bottle manufacturers to perfect the product, in 1892 Painter applied for a patent for his invention and in 1893, he founded "Crown Cork and Seal Company" , now named is "Crown Holdings Inc." , the world's leading manufacturer of corks and beverage items

As technology advanced, the bottle cap was also gradually refined. The material is changed from metal to PVC, the number of aliases on the cork and the height of the cap are reduced. However, the wavy border like the crown is still retained.

Surely you will be surprised to know that Crown Holdings, Inc. - Painter's company is still operating today. The company's headquarters is currently located in Philadelphia, USA.

After many adjustments, the number of aliases was eventually adjusted to 21 as today.

Why does the beer bottle cap have 21 aliases?

In fact, the first beer caps invented by William Painter have 24 aliases . In the 1930s, everyone used this type of bottle cap but later they found out that because of too many aliasing, the beer bottle cap was too tight and it was difficult to open.

After repeated experiments, the number of aliasing was eventually adjusted to 21 like today. But why are 21 teeth?

1. First , 21 is a multiple of 3. In the mechanical principle of physics, three points that support an object are more stable than two or four points. But applying the three-point rule to fix a round mouth has a very high degree of difficulty, so the cap needs to be a multiple of 3.
2. Second, the bottle cap must meet two basic requirements, one is carefully sealed, the other is firmly fixed. The 21-cap bottle cap satisfies both of these requirements.
3. Lastly , because beer contains a certain amount of gas. When opened improperly, it can lead to uneven pressure inside the bottle, injuring the user, the 21-toothed bottle cap can ensure safety for the user when opening the lid. Moreover, the wavy design of the cap not only increases friction but also facilitates bottle opening.

Due to the best performance in terms of tightness, rigidity and ease of opening, the 21-toothed beer lid has been perfected and has become an international standard.