Glass – what actually is it?

The foundations for your professional window cleaning

Generally speaking, you are dealing with glass when cleaning your windows – it makes sense, then, to get to know the material a little bit better. As #1 in the professional window cleaning trade, we at UNGER are very familiar with the properties of this surface. We would like to give you an insight into what glass actually is in order to make your window cleaning even more effective!

Appreciated for centuries

The oldest known ‘recipe’ for glass comes from the year 700BC – although there are many indications that glass and in particular glazes were manufactured much earlier than that. Glass is translucent, delicate and generally scratch-prone. It is made up of approx. 73% quartz sand, approx. 13% sodium carbonate and approx. 10% lime – the other 4% is made up of pigments such as metal oxides, for example. The quartz sand serves as the glass-forming raw material, whereas the sodium carbonate promotes the melting of the quartz. The lime gives the glass its hardness, sheen and durability. Glass is particularly popular, because it is almost completely resistant to chemical influences. It is for that reason that it has almost always been used for containers.

The large number of different types of glass comes from the different methods used in the manufacturing process – for example, the surface can be structured or translucent and colored. Window glass is generally made up of so-called float glass and is extremely resistant to atmospheric influences and scratches.

You may have seen ‘antique’ glass in older buildings. This is hand-worked glass which is easy to recognize from its bubbles and streaks. The surface of this glass is structured in such a way that it must be cleaned with leather. Incidentally, the same also applies to crown glass. It is translucent, blown and has round glass panes which are framed in lead. Window cleaning here should include prior washing and subsequent chamoising and polishing. Important: do not apply too much pressure!

So-called frosted glass is a translucent glass which is manufactured by etching or grinding. Much like milk-glass which is manufactured with white color pigments, frosted glass may be cleaned exactly like normal glass. You can find some useful tips here.

Particular caution is required when dealing with toughened glass or tempered safety glass (TSG), because it is especially scratch-prone. Small sand and dust particles can cause serious damage when washing the surface. You can find out how to recognize this type of glass here.

The general rule for window cleaning is that professional tools will significantly improve your cleaning results and considerably reduce the amount of effort required from you. This applies to both squeegee rubber blades as well as to using telescopic poles for safe working overhead and in high-up areas. You are always on the safe side if you use UNGER products, because we have been the market leader in the professional window cleaning trade for more than 50 years now. Benefit from our experience and turn yourself into a real pro!



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