Careful friends will find that if the things we buy are in glass bottles, there will be some words, graphics and numbers, as well as letters, on the bottom of the glass bottle. Here are the meanings of each.
Generally speaking, the words on the bottom of the glass bottle are the mold numbers. If quality problems are found after the glass bottle is produced, the problem can be found out according to the bottom number of the bottle.
Usually, the production equipment for glass bottles is: row machine, manual machine, pouring machine, and its process is that one equipment can combine multiple sets of molds, and the molds are composed of bottle mouth molds, bottle body molds, and bottle bottom molds.
Detailed explanation of the number production on the bottom of glass bottles:
The minimum order quantity for glass bottle production is usually at least tens of thousands. In order to increase production time, multiple sets of molds can be made to produce the same glass bottle. After the multiple sets of molds are blown and formed, they need to be put into the annealing furnace for gradual annealing and cooling from high temperature to low temperature to increase the stress between glass molecules. However, the glass bottles produced by multiple sets of molds enter the annealing furnace for mixing. We cannot distinguish which set of molds they come from in terms of shape. The numbers on the bottom of the glass bottle mold are usually letters or numbers. The letters are usually the abbreviations of the manufacturer's company name or the abbreviations of the purchaser's company. When the letter numbers appear, some numbers will generally appear, such as: 1, 2, 3, 4, 5, 6... etc. This number plays a very important role in the manufacture of glass bottles. During the packaging process, random inspections are carried out. If quality problems are found, it is impossible to determine the source of the quality problems in a timely and accurate manner. Therefore, different digital numbers are made on the bottom of the corresponding molds of each set of molds. When some problems are found, we can determine the root cause of the problems more promptly and accurately.
The graphics and numbers on the bottom of the glass bottle represent different meanings: “1”——PET (polyethylene terephthalate), which will produce carcinogens after 10 months of use. “2”——HDPE (high-density polyethylene), which is not easy to clean and can easily breed bacteria. “3”——PVC (polyvinyl chloride), which is easy to produce carcinogens when exposed to high temperatures and oils. “4”——LDPE (low-density polyethylene), which is easy to produce harmful substances at high temperatures. “5”——PP (polypropylene), a common material for microwave lunch boxes. “6”, PS (polystyrene), which is heat-resistant and cold-resistant, cannot be used in microwaves. “7”——PC and other types, used to make milk bottles and space bottles, but water cups made of this material can easily release toxic substances such as bisphenol A at high temperatures, which is harmful to the human body. Do not heat this water cup when using it, and do not expose it to the sun. Among them, only bottles above 5 can be reused, which means that bottles below 5 cannot be reused.
Post time: Mar-12-2025