The rainbow phenomenon sometimes appears on the surface of tempered glass. What causes this phenomenon? Let’s analyze it further below.
First, let’s analyze the reasons from the perspective of the original glass piece. Today's original glass adopts float production technology. During the production process of float glass, the tin ions in the tin liquid are absorbed by oxygen to generate stannous oxide (SnO), which diffuses into the surface layer of the glass in contact with the tin liquid. The thicker the glass, the greater the chance of contact.
Secondly, the production process of tempered glass needs to be carried out in a tempering furnace. When the glass enters the tempering furnace and the temperature exceeds 600°C, the tin oxide (SnO) in the surface layer of the glass is oxidized into tin oxide (SnO2), expands in volume, and forms microwave ripples. Under sunlight, light interference occurs, presenting a rainbow or mist-like thin layer dominated by blue.
Solutions to the rainbow phenomenon on the surface of tempered glass:
1) Choose high-quality original films and control the lower limit of heating temperature to reduce the generation of stannous oxide;
2) If it cannot be controlled from the original film, you can use the method of polishing the glass surface to remove the microwave ripples on the glass surface and eliminate the rainbow phenomenon.
