The reason why borosilicate glass bottles are hotly debated is that in early July 2020, when the COVID-19 pandemic was still very serious, Zhang Wenhong, director of the infectious department of Huashan Hospital affiliated to Fudan University, said in an interview: "The production of glass bottles for vaccines is more difficult than the vaccines."
Why does he say that?
That's because any drug will interact with the packaging material after a certain period of time. In order to reduce this interaction and avoid problems with the efficacy of the drug or side effects, ordinary glass cannot be used, but chemically stable borosilicate glass, and it must be a borosilicate glass bottle.
Medium Borosilicate Glass Bottle
So what is a borosilicate glass bottle? What is its origin? Why does the new crown vaccine use medium borosilicate glass bottles?
When it comes to medium borosilicate glass bottles, we have to mention borosilicate glass. It can be said that medium borosilicate glass bottles are just one category of borosilicate glass. Low borosilicate glass also counts, but there is a difference between the two. The main difference between the two is that it has a higher content of boron trioxide, higher thermal and chemical stability, and a better ability to withstand drastic changes in temperature. Strong, so the medicine bottles produced also have certain performance differences.
The national standard for water resistance of the inner surface of low borosilicate vials is 2.6m, and the national standard for water resistance of the inner surface of medium borosilicate vials is 1.3m.
To put it simply, "water resistance" refers to harmful alkaline oxides such as potassium and sodium that are adsorbed on the inner wall of the vial during the subsequent processing in the bottle factory. The fewer oxides, the better the water resistance. Good water resistance is good for the pH and clarity of the medicine. Various indicators such as strength and stability are relatively good.
The size tolerance of medium boron vials is very small. For example, the standard tolerance of the outer diameter of 16 tubes is plus or minus 0.14m. The color is crystal clear and the strength is also very high. It better matches the production equipment. The tolerance of low borosilicate is large and unstable between batches. For example, the positive and negative tolerance standard for the outer diameter of 16-tube tubes is 0.3mm, and the color is greenish, making it difficult to match imported equipment or high-end equipment.
How Many Kinds Of Borosilicate Glass ?
The classification of borosilicate glass has been mentioned in the previous article introducing "What is borosilicate glass?" and will not be repeated here.
The current situation of Borosilicate Blass
At present, in addition to the Schott company mentioned above, Japan's NEG and the United States' Corning also dominate this field. The market share of these three companies has reached 90%. As for China, although it has also introduced relevant equipment and sought the path of independent research and development, there has not been much breakthrough so far. There are still problems such as low product qualification rate and high production cost. Therefore, there is still great resistance to the large-scale production of domestic borosilicate glass, and it is difficult for us to achieve this in a short time.
Therefore, many of our borosilicate glasses are mainly imported. Among them, the largest import is Schott's BF33 borosilicate glass, which is widely praised by our customers.
Moreover , Schott is now actively investing in the construction of new factories and has two production bases in China, which will play a good role in promoting the development of China's medium-boron silicon glass industry.
