If improperly handled the integrity and properties of coated glass can be compromised just as with any normal glass. Therefore all production stages of coated glass, from storage to assembly, require specific handling techniques. Typically, these techniques are not difficult, but but require careful attention on the part of the glazier.
Not all coated glass has the same properties as there exist two different production processes: the pyrolitic, also known as the on-line process, and the vacuum or off-line process. As the name already suggests, the on-line process consists of applying a coating during glass production, also known as hard-coated glass. In the off-line or vacuum process, metal oxide particles are deposited on the cold glass surface by a chain reaction in a vacuum vessel. It is often called 'soft-coating', because the coating is more susceptible to damage than hard-coated glass.
Storage and handling
During storage, whether coated or uncoated, the glass is vulnerable to permanent surface damage in the form of staining. Staining is caused by a chemical change or degradation of the glass surface. Therefore it is important that glass be stored in dry, clean area, preferably at room temperature, with acids and other chemicals kept away from the glass.
The handling of coated glass, especially soft-coated glass, merits special attention. It is advisable to use clean, soft gloves in order to avoid damage to the coating.
Avoid any contact of the coating with metals or other hard materials (i.e., razor blades, rings, or other abrasive clothing or accessories).
When cutting coated glass use only approved cutting liquids in the recommended amounts. In order to prevent scratches it is advisable that the coated surface is kept side up.
As abrasive cleaners such as fluoride salts and hydrogen fluoride cause chemical reactions and degrade glass surfaces, avoid their use.
When running glass through washers, place the coated surface face up ? not down. Detergents that are normally used for non-coated glasses may not be suitable for coated glass and should be evaluated prior to use.
Keep the brushes in good condition and do not stop coated glass under the washer brushes. This can result in scratches.
Due to its ?fragility? soft-coated glass is usually used in insulated and laminated units facing the inside of the unit. In the IG units the edges of soft-coated glass should be deleted to produce a greater IG life.