There is a gap between Chinese medicinal glass bottles and international neutral glass standards

At the 10th Annual Conference held in Frankfurt, Germany, experts in pharmaceutical glass bottles proposed the main chemical composition, chemical stability, and physical performance technical indicators of 3.3-borosilicate glass and neutral glass. Among them, the chemical composition and physical and chemical properties of 3.3-borosilicate glass are basically the same as those of China's ultra-hard materials and GG17 materials. The main difference is that the control range of linear thermal expansion coefficient is different. China has not yet strictly defined the control range of linear thermal expansion coefficient for these two types of glass. The performance difference between international neutral pharmaceutical glass bottles and China's "neutral" glass is quite obvious. In the future, it is necessary to actively develop international neutral glass production and gradually limit the use of our original concept of "neutral" glass, which is becoming a consensus among industry insiders.

In China, low borosilicate glass is a so-called "neutral" glass that has been used for many years. Compared with international neutral glass, there is a significant difference in chemical composition between the two. The boron content of "neutral" glass in our country is relatively low, so the coefficient of linear thermal expansion is large, and the particle water resistance cannot maintain HGB1 level. This is because the "neutral" glass material in our country is relatively ordinary, so the water resistance on the inner surface is also poor. International neutral glass can ensure that the water resistance on the inner surface meets the requirements of ISO4802-HC1, while Chinese "neutral" glass is difficult to achieve. In the international standard ISO12775-1997 "Classification of Glass by Composition and Test Methods for Normal Mass Production", packaging glass is clearly divided into three types: international neutral glass, borosilicate glass, and sodium calcium silicate glass.

In this international standard, sodium calcium glass is not specified for medicinal use, while international neutral glass is recognized as the preferred glass for medicinal glass bottles worldwide. In the domestic pharmaceutical industry, it is also referred to as Class A ampoule glass bottles, 5.0 glass, or Class A materials. Here, 5.0 refers to its expansion coefficient not exceeding 5.0 × 10-6. Due to its water resistance, acid resistance, and alkali resistance being all Grade I, this type of glass can be said to have excellent chemical and thermal stability, As a medicinal glass bottle, it has incomparable advantages in ensuring drug quality.