Corning Restricted Method for Measuring the Chemical Heterogeneity of Glass Containers

The importance of the glass surface has received increased scrutiny in the last several years including the publication of the FDA advisory on delamination in 2011 and the introduction of the Glass Surface Test to USP <660> in 2012. In the production of glass containers, the forming process (converting) is the primary mechanism that alters the surface chemistry. Changes in the surface chemistry have important implications. For example, the generation of delamination flakes has been linked to the heterogeneous surface chemistry produced when glass components volatilize and deposit due to exposure to a flame. Current methods for evaluating pharmaceutical containers such as USP <660> and <1660> do not sufficiently define the variable quality that can be observed in containers that meet Type I requirements. Some shortcomings of current testing include: