Glass bottles are a widely used packaging container that plays an irreplaceable role in many fields such as food, medicine, cosmetics, and alcohol. The color, transparency, and other characteristics of glass bottles are also one of the reasons why they can be widely used. However, some special colored glass bottles require coloring treatment to be made. So, what methods do glass bottle manufacturers use when coloring glass bottles?

1、 Using metal oxides for coloring

The chemical method of using compounds containing metal ions to form a layer of metal oxide film with a thickness of several micrometers to several hundred micrometers on the surface of glass, which optically produces hundreds of glass colors, is called vacuum deposition. In this method, the selection of oxides is very important because metal ions can absorb electromagnetic waves of specific frequencies, resulting in special colors. Some commonly used oxides include:

The classic blue bottle glass used in iron oxide (Fe2O3) halogen lamps is colored with iron oxide.

Cobalt oxide (CoO) - used to make blue and green glass.

Chromium oxide (Cr2O3) - used in the production of jadeite green glass.

Cadmium oxide (CdO) and manganese oxide (MnO2) - can be used to make purple glass.

Copper(II) oxide (CuO) - used to make brown and reddish brown glass.

2、 Dyeing with metal ions

Dyeing can introduce metal ions on the surface of glass, which can replace other ions in the lattice and play a role in the light absorption of stained glass. Dyeing refers to the addition of metal oxides or silicates with similar properties but not completely dissolved into turbid glass, which are dissolved by heating. Due to the effect of temperature difference, they form Solid solution with low solubility in the glass; Alternatively, metal oxides or oxide precursors can be directly added to the solvent glass and sintered at high temperatures to form colored glass. The metal ions to be used include:

Iron oxide (Fe2O3) - can be used to manufacture brown, brown, and black glass.

Manganese oxide or manganese (IV) oxide (MnO2) - can be used to manufacture purple or orange glass.

Cobalt oxide (CoO) - used to make blue and green glass.

Copper(II) oxide (CuO) - can be used to make blue and green.

Chromium oxide (Cr2O3) - used in the production of jadeite green glass.

3、 Dyeing with organic imines

Traditional glass dyeing technology requires maintaining a certain temperature and waiting for a long time, while using organic imine dyeing method is faster, requires shorter time, and saves more energy resources. In this method, nitroimines are commonly used as colorants, which can react with the glass surface to form dye molecules that absorb specific wavelengths, thereby changing the color of the glass surface. Its efficiency is higher than many other dyeing methods.

4、 Using electrolytic color method

Electrolytic coloring is the process of using the inherent quality of glass to change the color of transparent glass by treating ions of different atoms. In the conventional electrolytic colouring method of thin films, the material is supplied to the cations in the glass to change the atomic size, shape and Coordination number, thus producing the optical effect associated with color. The advantage of this method is that it can form a fairly uniform transparent film on the glass surface, allowing for more uniform staining compared to other methods.

In summary, the above methods are the methods that may be used when manufacturing glass bottles with different colors. Of course, in practical operations, sometimes composite methods are used to complete color processing. Therefore, experienced technical personnel are required to operate the manufacturing and coloring processes to ensure better product quality.