色・発色
ionization tendency
Japanese: イオン化傾向
Order of oxidizability of metals. This underlies the behavior of nonferrous metals. / Note: K > Ca > Na… > Cu > Ag > Au
The order of metal reactivity. This underlies the behavior of nonferrous metals.
Note: K>Ca>Na…>Cu>Ag>Au
Learn More
Ionization tendency is a ranking of metals based on how easily they lose electrons to become ions. In the context of glass fusing, it is used as a fundamental concept for understanding “which metals react most readily with which glass components” and “what chemical reactions metal ions such as silver, copper, and iron undergo within the glass.” Metals with a higher ionization tendency react more readily within the glass and can cause unexpected color changes.
Coloring metals such as silver and copper contained in glass ionize at the firing temperature, migrate through the glass, and react with adjacent glass components. This manifests as a “silver reaction” or “reaction line.” By understanding ionization tendencies, you can decipher the mechanism behind “why color changes occur with this particular combination.”
Related Concepts
Studying these topics—the silver reaction, reaction lines, metal oxides, and coloring versus discoloration—together will deepen your understanding of the chemistry behind glass coloring.
This entry is written in Japanese by Rei Chikaoka and translated for readers outside Japan. If something reads oddly, the original is the source of truth.