Back in the late 1800s, William Pate invented and patented the 24-tooth bottle cap. The 24-tooth cap remained the industry standard until around the 1930s.
After the emergence of automatic machines, the bottle cap was put into a hose automatically installed, but in the process of using the 24-tooth cap was found to be very easy to block the hose of the automatic filling machine, and finally gradually standardized to today’s 21-tooth bottle cap.
Beer contains a large amount of carbon dioxide, and there are two basic requirements for the cap, one is a good seal, and the other is to have a certain degree of occlusion, which is often referred to as a strong cap. This means that the number of pleats in each cap should be proportional to the contact area of the mouth of the bottle to ensure that the contact surface area of each pleat can be larger, and that the wavy seal on the outside of the cap both increases friction and facilitates opening, with 21-tooth bottle cap being the optimum choice to meet these two requirements.
And another reason why the number of serrations on the cap is 21 has to do with the bottle opener. Beer contains a lot of gas, so if it is opened improperly, it is very easy to hurt people. After the invention of the bottle opener applicable to open the bottle cap, and through the saw teeth constantly modified, and finally determined that the bottle cap for the 21-tooth bottle cap, open is the easiest and safest, so today you see all the beer bottle caps have 21 serrations.
Post time: Nov-02-2023