A bottle is a narrow-necked container of various shapes and sizes that stores and transports liquids. Its mouth can be sealed with an internal stopper, an external bottle cap or a closure, or by using a continuous thread or screw-thread. Bottles may be made from glass, plastic, or a combination of both. They are also used in the manufacture of a wide variety of products, from pharmaceuticals to beverages, cosmetics and household cleaners.
Glass bottles have a unique chemistry and physical properties. They are non-equilibrium material that appears solid but continuously relaxes toward the equilibrium liquid state (See Glass Science). The atomic structure of glass is different than that of metals and other common materials like ceramics. Glass is also non-brittle, which makes it a safer and more durable container for chemicals than most other containers.
There are many different types of glass that can be used to make bottles and they all have specific properties that give them distinct characteristics. For example, soda glass has a high expansion ratio that makes it a good choice for bottles that will contain corrosive liquids such as cleaning solutions or oil. Other important qualities of soda glass include low viscosity, clarity and durability. Glassmakers combine a number of raw materials to create the desired glass composition, called a batch.
During the glassmaking process, the raw glass mixture is heated to very high temperatures in a pot called a crucible. This fuses the glass components together into a single mass of material, which is then shaped in a mold to produce a bottle. The forming of glass bottles can be done manually or automatically and is an extremely labor intensive and time consuming process.
A large portion of the bottle production process is a manual step, whereby a worker hand blows air through a tube, or parison, into the body of the bottle. The air is drawn out through the mouth of the bottle and the liquid or other product is poured inside. This type of production can be very precise and allows for a great deal of customization in the shape of the bottle and the size of its opening.
Another popular method of producing bottle is by machine utilizing the press-and-blow process. The bottle is formed in a parison mold then a second blow mold is used to form the neck of the bottle. This is the most commonly utilized automated bottle production method.
A bottle can take hundreds of years to break down into microplastic and enter the ocean, where it is swept away in large systems of rotating currents. The Pacific Garbage Patch is a well-known example of this. In addition, the use of a single bottle can lead to waste disposal issues that have not yet been resolved.
