Etching on both sides
Etching glass on both sides can enhance its characteristics. This approach is suitable for applications requiring a higher level of opacity or a similar finish and visual effect on both sides of the glass panel (e.g. partitions).
Most glass is produced by the float process. The raw materials – mainly silica sand, soda ash, and limestone – are melted in a furnace and then flowed onto a bath of molten tin. The glass then takes form and gradually cools as it moves from the tin bath to a controlled cooling chamber.
Float glass is best etched on the ‘air’or ‘atmosphere’side of the sheet, due to the greater likelihood of impurities and surface imperfections on the “tin”side. Production of acid-etched mirrors and two-sided etched glass requires etching of the tin side, posing an increased risk of defects in the surface if inappropriately done.
When considering double-sided acid-etched glass or acid-etched mirror, the type of finish specified impacts quality. The manufacturer of the acid-etched product can recommend the finish (if any) suitable for the application.
Exterior applications
Acid-etched glass may be appropriate for exterior applications, such as insulated glazing (IG) units, skylights, and balustrades. As acid-etching is not a coating, its resistance properties in outside conditions are essentially equivalent to non-etched glass. However, it is important to note an etched surface with rugged peaks and deep valleys could lead to higher maintenance costs because dirt particles may be harder to remove. Therefore, the use of an etched surface with a lighter finish (i.e. smooth, rounded bumps) is recommended in exterior applications. In these situations, the level and type of maintenance required is similar to that of non-etched glass.